I think OP is in the same position I was in when I sold my parents house. I interviewed 3 realtors who all gave me different comps. Comp is short for comparable , and if there were no comparable homes that sold in her area. All custom homes of differing sizes, ages, on different sized lots. So the comps really were a guesstimate of what the house was worth. I got comps that indicating the house was worth $495,000, $579,000 and $695,000. Throw in what I suspect would be a title problem OP has.....with the house actually extending over the property line.......you are probably going to need a Realtor and a Real Estate attorney to sort everything out to make is marketable