• synopsis contains spoilers -

Been trying to look for this manga forever and I can't find it, if anyone has any ideas I'd really appreciate it!

It's a poor uke x rich seme, and I think one guy works as a cleaner/janitor at this big company and that's how he meets the seme. There's also some kind of building buying/selling scam(?) that's a big plot point, and finally the most memorable thing was that the seme was revealed to be HIV positive and that's a big part of their struggle in relationships.

Thanks in advance!

Doesn't sound familiar, but this advanced search using the "HIV/AIDS" tag might help:
https://www.mangaupdates.com/series.html?category=HIV%2FAIDS&genre=Yaoi&filter=some_releases&perpage=50