Financing an unfinished house - after auction

[Dave Silva]

We recently sold a rental and have some cash- ($60K) we are bidding on a partially  restored farmhouse at auction. 

We are not investors at this point, my wife loves this house- dream house. perfect house - best house EVER. 

So if i win the auction at $100K i have about six weeks to settle up.  We could borrow from our retirement to close the deal then finish the restoration and do a cash out refi to pay retirement back. 

But with 50% down i'm thinking  there might be other ways to finance this?  My bank is a credit union, i've done two renovation loans with them and they are too slow. 

Can an amateur get financing on an unfinished property with 50% down?  I think the  house needs about $20K to be great. 

thanks