A low appraisal changes the math, but it does not automatically end the transaction. The right response depends on the loan program, contract language, comparable sales and whether there is a supportable basis for reconsideration.
The practical answer
Mortgage guidelines are detailed and change over time, so the correct answer is always scenario-specific. The useful question is not “Can this ever be done?” but “What is allowed for this borrower, property, program and lender today?”
