Short term mezzanine Financing for fully stabilized MFH

[Sol Bier]

Looking for suggestions for my situation. I'm close to putting a MFH (5+ units) under contract, and spoke with a few lenders able to loan 75-80 LTV (fully stabilized property).

Due to my unique tax situation, its better for me to purchase more units this year to take advantage of NOL rules. I will be ~ short 10% of the purchase price. I can sell some securities, but I don't want to incur capital gains by selling this year.

Are there lenders that will take subordinate position, for a 12-18 months term/balloon payment? I'm ok with paying 6-9% for this since its very short term. Loan would be for around 500-1M. 

Never done this before, open to suggestions on how to structure this.