When I tried making a trashcan for TS3 (I'm trying to make a park set), I accidentally made it over 4000 polys. How? When I made some cylinders, I forgot to reduce the slice and stack numbers.
This set is the highest I ever made, not on purpose mind you.
I had the cylinder slices on the bottom of the bed and endtable all the way around, what came to I think over 12,000 for the bed and over 8,000 for the endtable.
So I took most of them away, but the endtable still had about 4,000 polys. Yuk!