I had a weird problem with apartments and gravetombs. Once my sim died and I put the grave into one of sim's inventory, every time the load was loaded to play, this error came up:

Object id: 53
name: Controller - UrnStone Mover - Version 2
Stack size: 3
Error: Problem executing script (GetBaseLotId): Run-time:
Lot with id -1 does not exist!
stack traceback:
[C]: in function `getAptBaseLot'
(none): in function `GetBaseLotId'

I just pressed "delete" in the options (reset didn't work). And seeing as in the error "UrnStone" is mentioned, I concluded that it's at fault and I need to get rid of the urn.

So, I placed an urn on the floor and moved it to another lot (graveyard). After that my game imddediately glitched: I couldn't access anything in the apartment neither in live mode, nor in buy or build mode. Options didn't became greyed out, they just didn't work. And suddenly a message came up, that my sim still needs to rent that apartment! But of course it couldn't be done, since it was already rented, and there was no option to rent it.

I tried to load the lot again, and saw this error:

Object id: 343
name: Controller - Apartment
Stack size: 5
Error: Problem executing script (Apartment - Update Object Copies): Run-time:
(none):0: attempt to index a nil value
stack traceback:
(none): in function `ClearLotApartmentObjects'
(none): in function `ApartmentObjectsToLotInv'
(none): in function `Apartment - Update Object Copies'

Now I see this error all the time, and the lot can't be played, because no objects on it can be accessed.

My main issue is that I need to keep a few custom things created by my sims that are in that apartment. So if I move them out, then move in and rent the apartment anew, I'm sure these things will be gone Even with "rent furnished" option that can be accessed through cheats, I think those things will be gone, those things are not furniture...

Is there any solution to this problem? I need to access those things somehow, to put them into my sims' inventory in order to save them.

First, I should warn you that the errors that you are receiving indicate that your apartment building has a serious problem. The problem is not with your urn, but with the fact that the game has lost the association between the apartment building (apartment base) and the corresponding occupied apartments (apartment sublot). This could be an indication of neighborhood corruption; solving your current problem may not solve the underlying corruption.

Have you got a recent backup of your game? If so, the simplest solution by far is to restore from your backup.

I am currently researching whether there is some way to get your apartment back.

Unfortunately not, I don't have a backup I've never encoutered serious issues before, and that's years of simming, so I stopped thinking that having a back up is necessary.

I got that apartment working again by moving sims out and back in, but of course all their cusom items were gone. It's okay, though, I just hope there's no serious problem with the whole neghborhood. Because you might be right that there is. For one thing, no matter what I do, my sim doesn't get paid for her business. I don't mean that she gets paid zero, but that not even a message about business shows up at night! And when she calls to check in, the manager says that there's nothing for her to worry about, so she can't check in.

I'm going to try to move her into another apartment or house, and see if the same problem will exist. Corruption of the neghborhood is a scary thing to me, I've played a few families for many generations in it, even the townies are all made over, if I lose all a neighborhood with such a long history, it's a tragedy. It's very dear to me.

Maybe I just build apartments in a way that is wrong... I put the garden stuff outside so that my sims could garden, I put cat stuff outside so that a cat would live outside. But the apartment lots aren't supposed to work like that, I think.

And as far as I know, I did nothing wrong with that neighborhood. Only once, in very distant past, I deleted one sim from simbin, but that's all.

P.S. I just remembered a strange glitch yesterday. One of my sims started walking to one spot all the time while on community lot. I thought that the bug had something with her being forcibly interrupted from DJing, as the fight broke in. Then she went home, and she still was going to one place all the time, to a particular spot in the bedroom. Other sims were ok. I tried forcing an error and resetting her, that didn't help. So I deleted her, saved, then loaded that apartment again, and she was alright. Not sure that this piece of info is useful, but maybe you can judge from it if there's a serious sorruption in the neighborhood. I hope that it's just her being glitchy after running off to watch a fight in the middle of DJing.

Corruption can take a while to show up, so it's possible that the one sim deleted from the sim bin is now showing up corruption in unexpected ways. These strange glitches that you're having do not bode well. If you are having odd problems on different lots and with different sims, then the likelihood is that your entire neighborhood is corrupt.

I don't believe that you are building apartments incorrectly; people use a wide variety of formats without any problem. Are you using cheats to modify the apartment building after sims have moved in? I'd have to check for the name of the cheats, but I'm talking about the ones which allow building. If so, I would recommend that you avoid them, since they can cause problems.

It's also possible that your problems stem from bad CC. Do you have much CC? Have you added anything recently? Have you tried all of the steps in the Game_Help:Game_Problem^wiki FAQ, to see whether some of your problems are resolved by these techniques?

About that deleted sim: is there any way to fix all problems related to him exclusively? For example, kill memories about him, or unlink him somehow? To make sure that it won't catch up and cause troubles.

I build apartments correctly. I was afraid of activating buildmode after sims have moved in, so I never did that. It seemed to much of an abuse of the game to be safe.

Bad CC I did check, but couldn't understand if it's all related or not. So I'm still unsure. I removed all CC, too, and did all other things suggested, and so far there are no problems on my lots, with or without CC. Thanx for your help btw

I'm afraid that I don't have any further suggestions. Removing memories and relationships may help, but it might also cause more problems if you don't get them all. Perhaps someone else will have some ideas about trying to contain the corruption.