The poll we did back in early June on how many shoots PFRE readers do each year suggested that a large proportion (around 40% or more) of real estate photographers are doing real estate photography on a part-time basis.
While this doesn't surprise me, a couple of business articles I ran across recently explains why this is more clearly:
Over the years I've sort of figured this out from talking to people that were getting started in real estate photography. When I started this blog, at first it amazed me how much interest there was in real estate photography. But the more I understand this business the better sense it makes.
My conclusion is: that real estate photography has tremendous potential as a freelance profession where you can decide what volume of work you want. And you can do it geographically almost any place you want. These days it's more than just 20-year-olds that can use a job like this! Everyone can use this kind of job to fill-in where some other job is not bringing in all the dollars you need. Real estate photography is a very flexible business.