The protection works both ways. Purchasers regularly change their minds too.
"Please note that we do not have any authority either express or implied to bind our clients in any way and we must emphasise that neither this correspondence nor any negotiations had between our clients shall constitute a note or memorandum within the meaning of the Statute of Frauds until such time as both contracts are signed, exchanged and a full deposit is paid."
The above is the standard wording used in correspondence between teh solicitors until the deal is legally binding.
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