Re: House bidding advise..
You are just paying a booking deposit, which IS refundable. It is only the deposit you pay when signing contracts which is non-refundable. So you can still pull out if necessary if you do not, for eg, get mortgage approval.
As to whether you are mad to buy a house in this climate I have nothing to say- who knows? If it is a house you want to live in, and you can afford the repayments ( even if rates rise) then you should make up your own mind on it. There are people who will advise you either way.