John,
A good agent is going to make sure your pre-approved first. The first reason is because it could mean the difference of your offer getting accepted or not . No home owner is going to wait for you get this done after you submitted your offer. Some other buyer can come in offer the same as you and get his offer accepted because he was ready before you. Second you need to make sure of your buying power especially in this market where most buyers can't get approved for the loan. 3rd, so by doing this you will save yourself time and disappointment.
Cesar Garcia
Associate Broker, Residential Appraiser
Determined Realty Group of Keller Williams Realty Landmark
Office :718-362-5453 - Sun Mar 1 2009, 21:44