Assuming you signed a builder’s contract? Or did you sign a GCAAR contract? If GCAAR then you have an easy out. If builder’s contract then many times they have a clause that settlement can be delayed up to two years without penalties to the seller.

You mentioned “down payment has been in escrow” - your entire earnest money deposit is your down payment?

Do you have an addendum/written documentation that they’ll cover your rate increase costs?

Did seller choose the title company / or give you $ credit for going with title company of their choice? Or did you choose?