Would owner financing or private lending for down payment be same collateral?

I can now find private lenders for apartment complexes and hotels that will loan up to 85%.

The remaining 15%, I would fund with other private loans or owner financing.

Would this be using the property as collateral for two loans at the same time and thus not make sense?

If so, is there a way around this?

 

I work with a bank and a second mortgate is what I understand. But with a double mortgage, hmm, I don't think that is legal as far as banks are concerned. But maybe your lender is not a bank, right? So if they will agree to lend you money for the 85% of the principal value of the property, I'm sure they will get the title from you. So how are you going to make a loan contract with the 15% lender, what would be your collateral if the title is already collateraled to the first lender?