It's tough to offer a definitive answer given the limited info (what formula
did you use, for instance), but I'm going to venture that any broker would
consider your payment to include 'P&I,T&I': principal, interest, taxes, and
insurance, plus any home-owner association dues. The PMT function calculates
only the loan payment (principal and interest). Since the PMT function
calculates only a portion of the total monthly payment, it would suggest that
you can afford to borrow more.
Does the broker's site break down that $1000 payment to show the components?

"headly" wrote:

Calculating mortgage payments in Excel using the PMT function, is this wrong?
When I use the calculator on any mortgage broker site I get a different
answer to a simple question: What amount could I borrow to result in a $1,000
monthly payment. Excel's goal seek give $190K and others say $160K, why such
a big discrepency? TIA