Don’t just speculate. Have him run it both ways.

I had a situation, not the same but a little bit of the same concepts, where I was buying a $300K house and had like $260K. So I needed a loan no matter what. I got an 80% loan and received negative points (covered all my closing costs) and a really high interest rate, then paid off most of the loan right away and the rest of the loan over a pretty short period. It was great!