A bad idea for who?
The seller or the buyer?
A seller, presumably, wants to sell - but if there are any issues, if any, it may not be straightforward.
A cash buyer can ' take a view' on any (if any) defective title/planning matters.
A buyer, funded by a loan, may find a lender very stringent on any (if any) defective title/planning matters.
Or anything which may make compulsory title registration difficult, if not impossible.
Legal/architect (or engineer) advices required on both sides.
mf