My case, we were pre qualified, when it come to the loan origination, there was a hickup.
In the case of another family member, a grandparent was going to gift part of the money when a fatality happened and tied up the money for too long.
My friend went to look at a house asking $250k but the owners sold it for $100k.
My daughter is prequalified for $x amount but has savings to push the price upward if she finds the right buy.
If you are so disturbed by clients coming by, have a weekly open house. Different days and hours as many people will not be on your schedule.