I would love some advice from the pros out there - I'm really stumped on the best way to accomplish my goal...

I have two businesses and want to purchase an office building under a new LLC and lease space to my businesses.

However, what I really want to do is also have other tenants so that I will have multiple revenue streams. The building will offer short and long-term lease offices as well as conference room rentals and other rental-type amenities.

Also, my sister wants to partner with me, so we had originally planned a two-member LLC.

The local bank I use said this arrangement won't work if I want to get a 10% down SBA owner-occupied loan, because the ownership of the business leasing the building has to be the same ownership as the business buying the building (meaning I would have to be 100% owner of both - no partner). There's also a question of whether it makes sense for my business to lease 51% of the building (I really only need a small office for that business and the building is about 6400 square feet).

Would it be better for me to just negotiate a master lease with option so I will have 3 years to generate the 20% down payment for a conventional loan? Plus, less risky since the space has no tenants now and although I'm confident on the business model enough to believe I will at least break even each month and still enjoy the investment ROI and tax savings, there's always the risk that it won't do better than that or that I won't even be able to generate the break even revenue.

Or, is there a creative way for me to make this happen? The building is 900k so there's a pretty big difference between 10% and 20%. 

I've been researching a ton, but there's definitely not as much out there on commercial as there is for residential! Thank you for any feedback or ideas!!