too much turnover?

You want to look very carefully at the comparable sales (is the building price per sq. foot plummetting for some reason?), board minutes, reserve fund, history of special assessments and maintenance increases, and necessary upcoming capital improvements and how they'll be paid for. Look to see if anything is going on next to or around the building like some construction project that will go on for 5 years or destruction of views due to new building, zoning changes that will markedly increase traffic, etc. Yes, a lawyer should catch most of this, but there is no magic to it--you should be trying to do some due diligence also.

Thank you so much. That is very helpful.

We live in a 32-unit bldg that has had two sales each year for the last 3-4 years. We bought last year and I would not have been thrilled if that number was 6, for what it's worth. Good luck and do some digging for info.

I think it really depends on the building. I live in a new development about 4 years old and I think the original owners are starting to cash out because of the good deals they got and the market strength. If it is a scenario like that I would not worry (aside from fear of over paying).