We sure do get requests from buyers that want a single family home with in-law suites, but they are really hard to find no matter what your budget. Odds are better however, if your budget is $500,000+ then you get more of a selection, and for properties $100,000- $500,000. Sure they come on the market once in awhile, but there are so few in a very specific budget.
What communities offer them?
Two communities that come to mind, have garage apartments located back of the property located in Independence, Winter Garden and Laureate Park, Lake Nona. Both communities have new construction possibilities. If you really want a traditional single family home with the In-Law Suite on the first floor or one level, then consider Lennars Nextgen product. They are building brand new homes in Central Florida intended for multiple families. You can use they as guest suites, home office or man-cave. No other builder is venturing out with this floor plan option.