Testing the waters for a property

[Stephen Gilmore]

I might have the possibility of buying a treed lot for cheap between two houses. Looking at the neighborhood I believe that one of the two owners would want the lot. However, I do not want to buy it unless I know one of them would. What's the best way to find out if they would even be interested in it? Would mailers to the two houses be best? If I receive a reply then try to acquire the property? Thanks for any input you may have. Stephen