Hi there!
As a simmer who loves to build, navigating Build Buy Mode is a mess.
The Sims 4 did Build Buy Mode right by making more explicit categories so I want to model this after its organization.
Below me is a plausible breakdown of the Function Mode.
I plan to do Room Mode in the future as well as fix EA's object tags like enabling vertical shift and deletability, etc.

If you have any comments or suggestions, I will gladly take them into consideration! Let's recategorize the Sims 3 catalog!!!
Just keep in mind, I a full time college student so it don't worry if I don't update this as frequently. I definitely want to finish this project!
Tell me if you like or want me to change anything!

New Update!!!
Apologies for the long overdue delay, I've learned how to FINALLY get those new categories to work. For testing I added a WA boat into the boats category and it actually worked! I'll be trying to see if I can add objects to the new categories and see if I can do this without having to worry about learning how to edit an OBJD in a hex editor...

The Return from Hiatus!
Hi everyone! I'm finally back from hiatus. Since then I've been exploring new ways to make this mod way more interesting and complex by adding new categories rather than grouping objects into their vague default categories. If you want to follow or give me modding advice, follow my update forum. Hope to give you a greater update on the project soon!
Build Buy Modding Forum

UI Sort Priority
Have you wondered why Hovercars and Drain Pipes are last in their category? That's because of the UISortPriority! Because of that, I can "force sort" objects in vague categories like Large Appliances. The Sims 4 actually does this as well with different objects so I'm going to try experimenting with this. (UISortPriority will come in later versions)

Questions
Should reward items be located in the regular catalog or be in buydebug? Therefore if you still want them, they're in buydebug.

REQUIREMENTS:

• An updated base game
• The Sims 3: World Adventures (tomb category)
• The Sims 3: Pets (dogs, cats, and horses categories)
• The Sims 3: Showtime (stage category)
• The Sims 3: Island Paradise (resort category)

OPTIONAL:

• Buzzler's Build Buy Choker (if you want to see commercial objects on residential lots)

CONFLICTS:

• Any other mod that modifies objd/cfen files.

Updates!
I have finally (yay!) started working on World Adventures!!!!! In the mean time, check out the newest Base Game update!!!! I also figured out how to move objects to the categories added in Showtime and Island Paradise!!!!

PLUMBING
Sinks -> Counter Sinks & Pedestal Sinks
Toilets -> Toilets, Urinals, & All-in-One Bathrooms
Showers & Tubs -> Showers, Tubs, & Hot Tubs
Misc. Plumbing -> Fountains, Fire Hydrants, & Sprinklers

APPLIANCES
Large Appliances -> Laundry (Washer/Dryer), Kitchen Appliances, & Vending Machines
Small Appliances -> Countertop Kitchen Appliances
Misc. Appliances -> Grills, Trash Cans, Mailboxes, Laundry Baskets

SURFACES
Counters -> Counters & Islands
Cabinets -> Overhead Cabinets, Decorative Cabinets, & Hutches
Dining Tables -> Dining Tables, Bar Tables & Buffet Tables
End Tables -> End Tables & Accent Tables
Displays -> Shelves, Display Cases, & Pedestals
Misc. Surfaces -> Bars & Picnic Tables

COMFORT
Beds -> Beds, Lofts, & Bunk Beds
Dining Chairs -> Dining Chairs
Living Chairs -> Living Chairs & Rocking Chairs
Sofas & Loveseats -> Sofas, Loveseats, & Sectionals
Lounge Chairs -> Lounge Chairs
Misc. Comfort -> Barstools, Desk Chairs, Tents, Sleeping Bags, & Fairy Houses

ELECTRONICS
TVs -> TVs & Game Consoles
Computers -> Computers
Audio -> Stereos, DJ Booths, & Wall Speakers
Misc. Electronics -> Clocks, Alarms, Phones, Cameras, & Call Boxes

ENTERTAINMENT
Sporting Goods -> Outdoor Sports & Gym Equipment
Hobbies & Skills -> Logic, Music, Skill Inducing, Pub Games, & Arcade Machines
Parties -> Weddings, Birthdays, Party Decor, Fireworks, & Bonfires
Misc. Entertainment -> Magic, Photo Booths, Umbrellas, Canes & Recreation

LIGHTING
Table Lamps -> Table Lamps
Wall Lamps -> Wall Lamps & ITF Corridor Lights
Floor Lamps -> Indoor Floor Lamps
Ceiling Lights -> Ceiling Lights
Outdoor Lights -> Garden and Fence Lights
Misc. Lighting -> Street Lamps and Spotlights

DECOR
Plants -> Indoor Plants & Planters
Wall Decor -> Paintings & Posters
Mirrors -> Mirrors
Curtains & Blinds -> Curtains & Blinds
Rugs -> Rugs & Skylights
Roof Decor -> Roof Pieces & Architectural Elements
Sculptures -> Lawn Ornaments, Statues, & Sculptures
Misc. Decor -> House Clutter, Partitions, Umbrellas, Signs, & Town Clutter

STORAGE
Bookshelves -> Bookshelves
Dressers -> Dressers, Wardrobes, Vanities, & Clothing Racks
Misc. Storage -> Nectar Racks, Alchemy Shelves, & Treasure Chests

KIDS
Furniture -> Cribs, High Chairs, Potties, & Strollers
Toys -> Toys, Music Boxes & Toy-like Decor
Misc. Kids -> Playground Equipment

VEHICLES
Cars -> Cars, Trucks, & Motorcycles
Bicycles -> Bicycles & Scooters
Boats -> Boats
Misc. Vehicles -> Hover Transport, Brooms, etc.

PET ESSENTIALS
Cats -> Cats
Dogs -> Dogs
Horses -> Horses
Misc. -> Aquariums, Cages, Terrariums, & Other Pets

STAGE PROPS
FX Machines & Lights -> Stage Lights & Effects
Stage Props -> Showtime Stage Props
Misc. Stage Props -> Late Night Gobo Lights, Strobes, and Dance Floors

RESORTS
Misc. Resort -> Resort Exclusive Objects Only

DEBUG
Tombs -> Tomb Exclusives
Underwater -> Diving Area Exclusives & Beach Debris
Fishing -> Fish Spawners & Mounted Fish
Gardening -> Seed Spawners & Gardening Plots
Metals, Gems, & Rocks -> RGM Spawners
Insects -> Insects, Nanites & Minor Pet Spawners
Misc. Objects -> Misc. Town Decor, Shells, NPC Cars, Debug Objects, Special Reward Objects, etc.

COMMUNITY
Buildings -> Functional Rabbit Holes, & Large Decorative Buildings
Misc. Objects -> Commercial Duplicates, Festival Exclusives, Rope Barriers, & Cash Registers

GARDEN
Trees -> Trees & Large Shrubs
Shrubs -> Shrubs & Wide Shrubs
Flowers -> Groundcover, Flowers, & Bushes
Rocks -> Reasonably Sized Rocks

BUILD MODE
Doors & Windows -> Doors & Windows
Columns & Fireplaces -> Columns & Fireplaces
Fences & Gates -> Fences & Gates
Modular Stairs & Railings -> Modular Stairs & Railings
Elevators -> Elevators
Spiral Staircases -> Spiral Staircases, Poles, & Ladders
Fountains -> Water Emitters
Pools -> Pool Ladders, Diving Boards, & Mosaics

WALL/FLOOR COVERINGS AT A LATER TIME

If you have any comments or suggestions, I will gladly take them into consideration! Let's recategorize the Sims 3 catalog!!!
Tell me if you like or want me to change anything!

Special Thanks:
Tizerist for inspiration on his' recat mod
http://www.nexusmods.com/thesims3/mods/1/?
The Simlogical for the in-game recategorizer and batch resource editor!!!

I would include sprinklers in misc plumbing.
(And don't forget the fairy houses which can either be deco or comfort depending on whether or not you are a fairy....)

Great idea!

A lot of objects need to be brought out of the misc and buydebug categories and put into the right place- even if they're deco- for example, fountains, drains and drainpipes could be dropped into the Misc. Plumbing category to further clean up the sculpture category. Ductwork could go into appliances, etc.

Same thing goes for the gardening category with everything being dumped into the tree category.

Tizerist did something like this, but I think there's still room for improvement!

http://www.nexusmods.com/thesims3/mods/1/?

Oh! yes there are a lot of objects that are either hidden and non-hidden objects that could be useful and be added in the buydebug category.
I'm just wondering about one thing though. When it comes to objects like sinks, etc. I guess it's pretty much organized so why should that one be fixed? Or is this meant for like objects that fit in two categories?

Oh, I like the idea of a more organised catalogue!
It would also reduce the loading time for some categories (Misc. deco, I'm talking about you), if items could be more equally or better organised.

I know that items are also ordered by price in the catalogue, so maybe something with that could be done to either regroup objects of the same genre or from the same set (example, all easels in the same price range, then all chess tables, etc.)?

While that would be great, I not really sure I want to change object prices unless I move it out of the debug category. Tizerist from NexusMods reorganized and repriced objects in his recategorization mod. http://www.nexusmods.com/thesims3/mods/1/?

However there are somethings that bother me about his reorganization and others I have seen so I want to make the catalog logically organized. Mine is partially inspired by how the Sims 4 categorizes objects, but applying a similar method to the Sims 3. Since we don't have a search bar in the Sims 3, I want objects to be located in logical categories rather than a vague mess like the current misc. decor.

I have no comments to make other than my agreement.

I'd like stuff to be organized together, particularly the decor. I don't know how many times I've looked for the kitchen decor, ie. knives, spices and dishes. Flipping through the misc. decor five or six times, give up and than find the exact dish I was looking for while decorating another room.

I think that clutter could be even assigned as per category of assumed use.

I.e. kitchen knives and containers could be assigned in the Misc Category of the Appliances folder- since they usually would be used in a kitchen setting.

Only truly generic decorative items would be in the Decor folder.

I think some Misc decors could be moved to sculpture to be honest. I mean, there are some wood-looking statues in there, or at least wooden objects that would fit the sculptures better.

But I agree with @jje1000, Clutter could be assigned as well. It would have been better actually if making a new group/category was easier, so we could add some more organised categories to it. Especially when it comes to decor. >-<

Shoot when it came to clutter I'd be happy if it was even just grouped together so I knew okay I just have to scroll down x way to get kitchen clutter. But I love your idea @jje1000

Hey look I'm a field researcher now!

Is there a way to add a new category? The page where pets stuff and stage stuff are located is almost empty.

In theory, it is possible. But then you also need to make the tabs fully work properly, unless EA give it this ? sign like with buydebug. And then there is the fact that we need to make it work within S3PE to see it as a game file that's just adjusted. (If you want to reassign everything within a new category within S3PE, it's pretty much helpful).

The only way I can think of is that misc. stage props and misc. lighting normally are hidden categories. I can enable them by placing objects in those categories. Otherwise I don't know how to add more categories. I would if I could... decor, electronics, appliances, storage, commercial, etc.

Hi Blyss. Yeah that's exactly what my mod does.
I'm open to suggestions on improving the mod. It's always a WIP and the new version will be tidier again.
Good luck with this, though. It could be interesting to see another persons take on how to do it, or we could even help each other.


Noted.

You say you don't want duplicates in the catalog. What's wrong with that? Granted, you don't want to do too much of it, but there are cases where it makes sense, such as with the items that are different between residential and community use. Or when two rather different categories fit the same thing. (Although why EA decided to classify a sprinkler as either entertainment or an appliance, but not as plumbing, still mystifies me. ) (No, I'm not obsessed with sprinklers. If I were, I would not still automatically look in Misc Plumbing for them, but I've been doing that ever since the tab first appeared. At least now it has hot tubs in it.)

If the object is available in the game, it should be somewhere in the catalog, even if it doesn't have a description. Otherwise, how is it going to be able to be placed?

I would have service vehicles in Debug. You don't want random neighbors deciding to drive around in them unless they are authorized to have one.

Toys in the catalog would be handy.

Mailboxes and trash cans are appliances. (Ok, I suppose you -can- use them for short-term storage...but it's not recommended to store anything you want to keep.)

Reward objects, relics, etc. in Debug. You don't want it to be too tempting to just buy them, but storytellers might need access to them.

Decor cabinets and anything that looks like it should hold stuff, but doesn't without an OMSP, would go in cabinets. By this time we should have all learned that anything in that tab is non-functional and useful only as decoration.
Shelves, alchemy cabinets, etc. that actually hold stuff... Storage or display are equally appropriate.

I don't have Pets or Showtime, so I have no real opinion on where pet supplies or show props should go, but putting them in their function tab sounds logical.

Misc.Plumbing currently has 3 hot tubs in it. Putting fountains, pipes, etc. there would make them easier to find, and give that poor tab more to do. But I think I might leave the Hot tubs there, as much as I would love to have one in my own RL bathroom.

Kid's Decor should be in with regular decor, and just separated by room. Especially now that we have fairy sims who might like butterflies and trees all over the walls.

Thank you so much for replying! This helps so much for recategorizing objects. It now makes sense where objects should be categorized. Multiple categories are make sense for some objects. Also, in the complete Sims 3 without store (I don't really use store content) there are eleven hottubs. If a category seems bloated I can use the UISortPriority to make it easier to find objects grouped together. Thank you again!

I'm flattered to see you comment, Tizerist because you currently have the best recat mod out there. I wouldn't mind working together with you on this mod.
I just don't understand why EA categorized the catalog so poorly. Yes, the game catalog developed over the years with new catagories, but TS4 base game fixed a lot of these ambiguities. There are some flaws bb.showhiddenobjects , but it is mostly catalogized pretty well.

Essentially, it boils down to: the management didn't care.
It wouldn't have taken much to dedicate a team member to keeping this tidy, but ea thinks in £££ only.

Nice word!

The first beta of the mod is available! Testers and feedback wanted!

Mod includes...
- Recats of the base game
- Unhidden rewards and misc. objects
- Some repriced objects
- Vertical shift for curtains, TVs, cabinets, etc.
- Many more...

WORLD ADVENTURES COMING SOON!

So you're doing these on a per-EP basis? What about the SPs?

I am also doing stuff packs. I'm either thinking of doing it with the following expansion. (HELS w/ AMB) or separately (HELS then AMB). I will be doing all of the packs from base game to Into the Future. I might be doing each pack and then at the end include the UISortPriority to force sort the objects by type. I want to develop what is in each category before I sort them properly.

I wish I could do the store content too, but recategorizing store content is very convoluted and there is way too much.
Unlike other modders I don't know how to fix stencils or unlock hidden stencils so I can't do that either.

I'll do World Adventures and then move on to High-End Loft and so forth.

Alright, sounds good! I wouldn't personally do a stuff pack and the following expansion, but alright.

It's funny actually, i'm working on a familiar project but for CAS. So I guess with both projects being released at some point, it could be a great change for the game's category for everyone's games

Let me guess, you're sorting everything by type. Jackets with jackets, pants with pants etc?