How do you go about choosing a REIT to invest in?

Do you understand the quirks of REIT accounting, particularly FFO and aFFO? If not, the NAREIT site is an excellent place to start, and a great overall source of info.

You will find that almost all Wall Street estimates and commentary is based on FFO rather than EPS. It is also important to your own fundamental analysis, a topic whose complexity is worth several PhD theses.

In my experience, Green Street Advisors is the most respected REIT analysis firm. Very expensive, but occasionally quoted in Barron's and other public sources. Worth reading any commentary.

Then you need to consider the sub-industries within REITs; Office, Malls, Medical, Residential, Storage, Mortgage, etc.

For most people, it is a better decision so buy a low cost REIT index fund or ETF from Vanguard.