Only yesterday I had the frustrating experience of having advised a client to delete a couple of unfair conditions from a contract, only to have the estate agent refusing to "allow" the purchaser to submit his offer the way he wanted to, and then after referring the matter to the vendor's lawyer (that's right a lawyer, not a conveyancer) the lawyer wrote to us to say that the estate agent would be handling all matters associated with the contract.  For goodness' sake, the lawyer drafted the conditions in the contract, the estate agent doesn't understand them, and yet neither the lawyer nor the estate agent will allow the purchase to submit his own offer on his own terms.  And does the vendor know that he's likely to lose a sale over this unfair but unnecessary contract condition?  No, I don't thins so.