Why don’t British buyers start demanding contingency or option-type contracts once the sales price is agreed? Is there any barrier to entering into a contract that gives the buyer the sole right to purchase for X number of weeks?
No, according to my UK lawyer friends, acsenray, there isn’t. It just Is Not How It Is Done.
This is interesting; we also have the statute of frauds in the US. See, for example, California Civil Code section 1624, which states among other things that a contract for the sale of real property is invalid unless it is in writing.
As acsenray and Billdo noted, in the states we deal with the difficulties inherent in a real property transaction by having written offers with contingencies: the Loan Contingency, the Appraisal Contingency, the Physical Inspection Contingency. And the title search is part of the whole shebang, too.
Interesting. Thanks for explaining all that, you guys. I truly thought my friend was having me on. I guess I owe her an apology. 
That I understand from the discussion. However, the job of a lawyer is to give their clients legal options and to craft arguments that fit the circumstances.
There isn’t what? Are you saying that such contingency or option contracts are illegal? Provided that they aren’t actually illegal under English law, if enough buyers start demanding them, then sellers will eventually start having to concede.
The key here, really, might be what Mangetout said. An individual buyer doesn’t have enough stake in changing the system to start insisting on contingency contracts.
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Inept inexperience lawyers, you mean? Perhaps named ‘Blair’?
Yes, thats true, but we make up for it by having the crappy ‘offers over’ system. House advertised for sale at ‘Offers over £120k’, Offer £140k and you don’t get the house cause someone has bid £141. It sucks, never know whether you’ll get the place you want, never know how much to offer, no chance for a simple negotiation or open auction.