Good idea about by-passing the realtor fees.
Realistically, it is worth more to you than to someone else. If you want more land, don't want to risk whatever you may get for neighbors, then as thatguy said, buy it and don't look back.
We bought an adjoining lot two years ago. Mostly to keep open buffer around us. There is a two acre lot enclosed on three sides by ours with an old house and falling down sheds. I will buy it too if I get the chance someday. A nice 94-year-old widow lives there, says she is planning on dying there. She is a good neighbor, but ya never know about the next one. It could be a nice young family looking for a starter price house, or it could be junkers and meth cookers.