Joint Venture With Vesting Contract

[John C.]

Hello,

I own over 100 properties in PA which I've acquired using mostly standard bank or DSCR loans. I have a private lender who has loaned me about 500K so far. We have a good relationship.
He and I are going to be purchasing a house together to use as STR. We will be acquiring a DSCR loan for acquisition. He is funding 100% of deposit and closing costs. We are forming an LLC with him as 100% owner. The day after closing of the property he will transfer 10% of his ownership shares to me. Each year he transfer the correct percentage of his shares to me to make me a 20 percent owner at the beginning of year 1, 30 percent at beginning of year, up until I own 50 percent. I do not want to do this through an operating agreement as it might create complications with the lender. What is the type of agreement we should be signing. Does anyone have a template? Or even the name of this type of agreement. What would I ask a paralegal to create? a Joint Venture Vesting ownership agreement?