I would stay away from realtors unless you work for them personally. I have had a difficult time dealing with them and collecting from them (in general). I do have several that are personal customers and there is never a problem getting paid from them. If I do not know them personally I must receive "funds in advance" before I will do any work.
My worst case took me 3 phone hours over 4 months to collect.
Emerald Green Lawn Service
Las Vegas, NV