Deposit $5000. 

Some states require you to have a separate bank account for tenants security deposit, if not, one is fine.

so send copy of paperwork back and ask for your full deposit as outlined in said copy of paperwork...

Maybe adjust the deposit to offset the risk? 

However, would I lose my deposit if my lender refuses to lend prior to the 30 day period because the roof hasn't been fixed yet?

So next year I will have at least £35.000, to put down as a deposit - and the old man (my dad) might also want a piece of the cake - as he is very interested in property as well.I've got my dad to join me on the mortgage - as bail (I'm not quite sure that's the english word for it.)What do you think about my strategy?

She already signed a nine month lease and paid her deposit and first months rent on time.

This was after a few verbal commitments that applied but never followed through, and one couple that applied, put a deposit, then decided not to rent the place.  

great job @Israel R. keep it going, you have chose a great market for your multi family investment.I had this problem before with a 26 unit deal In San Diego back in 2012. almost lost the deal (and a 100k NON Refundable deposit) due to not addressing correctly the management companysorry I have none to recommend in Columbus right now , but wish you much luck!

The only thing you need to do is deposit the check and track your income and expenses for taxes