Of note, a little off topic: We purchased our house for $146K back in 2001, a hell of a deal/steal. If we stuck with the original mortgage, we would have paid about $180K in interest, More than the value of the house at purchase time. Back in 2001, it was our first house, and we couldn't get a reasonable interest rate.

Go here to fart around with various loan parameters:
https://usmortgagecalculator.org/

So original loan at 6.8% over 30 year would have cost me $180K
Same loan a 3.99% would have cost me $94K
Dropping to 15 year at 3.99% would cost me $43K

So from original to now not considering the 7 years stuck on the crap loan it would be a $137K pond! Out here, I would need more than 16 acres to support that.