Do get three different estimates. If possible, ask around your
neighborhood and see if anyone has had their house painted in the past
three years and if, yes, perhaps you can get their number. (Assuming,
of course, they are good) Word of mouth is usually best way to find
out about how good a job they do and if it lasts. Paint stores tend to
recommend their customers - for obvious reasons.
If you have a consumer protection bureau in your county, be sure and
check with them before hiring anyone. See if any complaints have been
filed against the painter you want to use....make sure that he (they)
is licensed and insured.