Getting back to the OP's issue - is it really subject to valuation or is it an unconditional contract? Sounds more like the buyer's finance is conditional (the condition that the buyer achieved finance is satisfied) however valuation finance prior to completion is not a factor in determining...
You could also add Pinkboy's moderator thread on April fools day too.
Not funny at all but interesting for the disparity of views of the members: this one
Purchasing purely on the basis of losing money is not a strategy. It is a plan to lose money.
Look at properties based on their cashflow, potential cg etc but do not use tax benefits as the main criterion to invest. If you do, go out and purchase olive groves, new growth forests or some other...