Drywall entrance to living room

Hi – Looking for advice! We are renovating a condo that we purchased to use as a rental. The building is all cement, and was built in 1987. All the units are comprised of two floors each. The ceilings on the second floor of the units and floors on both levels are concrete. The second floor ceilings have popcorn :eek:, which is nasty, old and dirty looking, so we’ve decided to remove it from ours. When we removed it in the bedroom (second floor), we discovered an area in the ceiling that may have had some prior patching done, which started crumbling off when we removed the popcorn (looks like it may have had water damage in the past, as there some small areas that are black in spots) leaving a really uneven surface with gouges. We would have liked to put sheetrock over the cement ceiling for a cleaner look and to hide all the imperfections (it’s not at all smooth), but the ceilings are very low (7’) so we don’t want to lower them even more. Instead we are thinking of just painting over the cement ceilings after repairing the area that is crumbling. Does anyone have recommendations as to what to use (and how) to do the repair, and what kind of paint can be used over concrete? Also, any suggestions other than painting without having to lower the ceiling further would really be appreciated! I can provide pics if needed. Thanks in advance for any advice!

I moved into a loft apartment where the cinder block walls meet the ceiling in a not so nice way (see attached image). I'll be painting the wall, is it advisable to do something about this ceiling joint? Should I put caulk in the spaces or is that a bad idea? Thanks