Understanding seller financing terms

[Alexis H.]

Hey BP!

I’m having a hard time understanding terms of seller financing. Particularly the 4.125% interest rate on $174,000 for 27 years and how $1,584 comes into play;

Scenario:

Down payment amount required 20,000. 4.125% interest rate, $1,584 monthly total and 27 years finance of $194,000.

Also, when doing a seller financed deal, is the price of the property negotiable or is it what the seller says it is since it is through seller financing? Thanks!!