I want to upload the houses I built on the Sims 2 but I don't know which items come from each expansion and stuff pack, that's why they keep getting rejected by mod the sims for download. I don't use custom content for my houses. Can anyone help me!! I've been researching about this for months.

Open up your cheat box, and type this into it

boolprop showcatalogepflags [true/false]

This will add as small flag to each catalog description of an object or item (not wallpapers or floor tiles though, sadly) that tells you which EP or SP something originally came with. So far as I know, there isn't a way to retroactively do it on a fully furnished lot, but if you have the cheat turned on as you're building, you can keep track of whether you've used a specific EP or SP much easier than any other way I (or anyone else that I know of) have found.

Hope this helps!

when you upload a lot on MTS you have to tick which of the EPs and SPs that you are running in the game that you built the lot in. So I see from your profile that you are running all EPs, so when you upload tick all those boxes and tick the SP boxes that apply to you too. (Mansions, if you have it, acts like an EP.) Don't worry about what item comes from what EP/SP.

If you want to practice uploading and get some feedback on your houses/lots why not post in the Creator Feedback Forum.

Would this also apply to apartments

It applies to any lot you upload. If you loaded up with an M&G splash screen and saved a lot to file, then M&G is what other people will need to be running to use your lot, even if you only used base game items. The items don't matter, it's the game engine which determines if people can use your lot.

I would also recommend like karen said, using the Creators Feedback forum before uploading your first lot.

Thank you so so much

Sorry to be a bother but would this also apply to sims or do i just list which expansion or stuff pack the clothes they are wearing are from

I think you need to read these guidelines. I have never uploaded a sim.