急问: 买short sale 房子(星期二要与屋主签合同).

急问: 买short sale 房子(星期二要与屋主签合同).
1. DO i need to put earnest money when i sign the Contract with the Owner. If yes, how much. If the bank do not approve the offer and things did not work out, Can i get my earnest money back?
2. 我什么时候应该开始申请loan.after sign the contract with Owner? or after i know bank's approval.补What is the time period between bank approve the offer and the closing data. 问的原因是sell's realtor told me that the bank normally allow only about 7 days to close the house after they approve the offer. if i apply loan after i know the bank's approval, i do not have time to get the loan. but if I apply loan before bank's approval, If things do not work out(high chance for short sale), i still need to pay the loan application fee if this is the case.
3. 我应该在什么时候inspect the house, after sign the contract with Owner? or after i know bank's approval.
4. 我应该在什么时候has the layer review the Contract, after sign the contract with Owner? or after i know bank's approval.

Thanks for your answer.