Trying to sell my car, buyer giving me trouble

I am trying to sell off my 2010 Ford Fusion with 200k miles and a transmission issue for $3,000 and haven’t got any luck in getting potential buyers until today when someone offered to pay me for the car but I need to sign over the title to his name before the purchase and he also wants to pay with Affirm. I asked him how it would work and he said he would just pay me in 4 installments every 2 weeks like how Affirm works. Idk if this is normal with marketplace someone help me!

It almost seems as if he is trying to pressure me into handing over title early and he’s asking to use a really weird payment method so I don’t know what to make of this.