Definitely shop around to different lenders. Try a small local bank (i.e. Cambridge Savings, Winter Hill Bank) a mid-size bank (ie Century Bank, Leader Bank) and a larger bank (ie Citizens). You will find rates and programs [and subsequently down payments] vary from lender to lender. The good news is you'll be able to find something that best fits your needs and wants.
Jen Keenan, ePlace RE
Central Square, Cambridge