I think that the cost of a trigger job depends on what is causing your trigger to be so heavy and the make of the firearm. For example, I made the mistake once of buying a S&W Sigma. I don't think $1000 would have bought me a good trigger on that POS. I'm content now in just buying guns with good triggers off the shelf, takes the unknown out of the equation, if you know what I mean.
My last purchase was a Kimber, nice trigger out of the box.
Blue Skies,
MaterDei