I think you know the answer. Unless you can sell your own house, you are not a practical potential purchaser for any property. You are a wannabee potential purchaser.
I think if you are serious about moving, then you should try and sell your own house ( and you may well be horrified at how little interest there is in it) and only when you have sold your own house, can you consider having an offer accepted on any other house.
Unfortunately, this is not what you want to hear but it is the reality of the current economic climate. The old days of bidding on a new property in the almost certain knowledge that your own would sell are gone. And yes, it is hard to co-ordinate sales and purchases with so much uncertainty.
mf