I live in a 114 unit condo, and we have social events regularly. But first, accept the reality that LIABILITY is a risk that you always have and cannot avoid. However, in my opinion the goal is to mitigate risk. If people live in the same place that the event is being held, then driving should be eliminated as a risk; that is a big win in the area of liability.
Is the condo providing the alcohol? If so, the condo should be serving the alcohol and abiding by the same standards as Pro-Serve (while not required, a suggestion of mine would be that one or two people / volunteers consider becoming Pro-Serve certified. ; not self-serve. About 8 hours of on-line with exam; $25 maybe is the cost). The knowledge would be helpful and the condo reduces risk.
A social with bartending may limit everyone to 1 or 2 drinks. Enough for a wine and cheese.
Or, is it BYOB? Somewhat different then. But again there is some responsibility to monitor consumption, and obviously assist if someone needs some guidance regarding their condition.
To a great extent, your event is not likely any different to a resident having a house party and being a fully responsible host.
Manage the risk down, and up the community experience and spirit.
My thoughts. Hope this is of some help. Best of luck ,,,,./David