Is this a good deal for funding first rental?

[John Korinke]

Hello everyone, I'm looking to get my first single family rental property soon and was hoping to get some advice. I was planning on borrowing a 20% down payment along with rehab costs from my mom and giving her a 12% return on whatever she lends me. And getting a conventional loan. I'm hoping to be able to pay her back in full after a cash out refinance. If I can't pay her back in full then she would get the cash flow until it's all paid back plus 12%. Does this sound like a good deal for both of us or am I overlooking something? Is she allowed to give me that much money or do we need to be in a formal partnership? I believe you can only gift someone in the range of $14k? Thank you for your help in advance!