Ruffian
We seem to be at cross purposes here.
The usual choreography is
1) Buyer and seller go sale agreed.
2) The buyer gets a survey done and may proceed, pull out or seek a lower price based on that.
3) Seller's solicitor sends contracts to Buyer's solicitor - and again, the buyer must be happy.
4) The contracts are signed and then everyone is committed.
Sure the buyer can put in anything they like "subject to finance" "subject to planning" "subject to Donald Trump getting elected" but the seller would be unlikely to agree to any of these if there are other buyers around.