There's probably only three practical ways you can get 100% financing.
The first is to buy the building cheap enough that the bank will fund 100% by making a portfolio loan. Or getting the seller to finance all, or part, of the transaction, that a bank won't finance. Or third, taking title to the project "subject to" and refinancing the existing loans. The bank will finance up to 80% of the value, depending on the performance history of the property. The downside to refinancing is that lender often require the borrower to assume personal liability for the new loan.
I would contact a commercial loan broker and ask his advice on this.