Your home buyer can back out from purchasing your property by utilizing their loan contingency.
.
What that means is that if the buyer cannot get a loan, they can back out and still get their deposit back.
.
However, this has to be done during the loan contingency period. Loan contingencies are usually 21 days long and start when you have an executed purchase contract.
.
If the buyer releases their loan contingency on day 21, they can no longer back out of the deal because of their loan contingency.
Pre-approval letter: Banks vs. Broker
Mortgage brokers may be able to provide you with more home loan options over a traditional bank.
.
I suggest you get approved with a traditional bank and a mortgage broker at the same time.
.
Compare the interest rates and fees both lenders are charging you... then choose to work with one or the other.