Zach, your deal was 50/50 with him providing funds, period.
Where he gets his funding is irrelevant. That assumes you will not be on the loan. However, if he encumbers the or your property, now you are assuming additional risk, what if he drops over and is incapacitated, blabbering in a nursing home from a stroke and his loan is foreclosed, you could lose the property.
So, it's not the same deal, it's one thing to not pay a partner, it's another not to pay a secured lender.
In reality, while he is having you at risk, you are contributing nothing to funding the deal, so even at that point, 50/50 could be fair, just realize that his leveraging the deal puts you at greater risk and perhaps gives you more motivation as well to perform.
Additionally, he can circumvent the partnership and take any obligation in default and follow through with remedies under that loan, outside your partnership. So it places him in a somewhat better position and he avoids any default/foreclsoure.
Another issue, a HML making a loan as an outside lender and taking an equity position is not only unethical but can be self dealing. The practice is illegal here. A lender outside of the business entity is a straight lender. A partner inside a company who lends money to the company is an entirely different situation and is common practice, but as a partner, accepts the risks inside that entity as well which an outside lender does not. Don't deal with HMLs who want that arrangement, IMO. In commercial arrangements, profits can be assigned as premiums, but I really doubt any small HML follows such premium structures based on the balances. Anyway, not sure this even applies as it wasn't clear, but sounded like the HML also wanted a slice. Another issue with those having money or access to money to lend and being unaware of the liabilities of lending or good practice being over shadowed by greed.
If you end up with a loan, you might consider signing the note too and justify any modification to the split if you can based on your risks assumed. But again, he who carries the water takes the first drink. Just my thoughts... :)
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