tell the estae agents from aruond the way that you are looking to sell but don't know how much to ask for
that way you have given them the bait and they will flock round in their multitudes

if they ask wehre you are moving to so they can flog you another property just say "abroad" and end with it there

if the house sells at least you've got a few different valuations on it, and if they go higher and lower then you can pick and chose