After reading another post on LBS purchase and service, is it possible LBS price includes later adjustment for cable stretch and REI price doesn't?

Though if so the LBS should tell you to come back in a few weeks.

My dad was a plumber, and he always fixed everything himself, (though working on bikes with pipe wrenches really messes with their paint jobs. ) I've inherited his DIY or is it DIX gene. I figure I need to buy a tool ONCE, but I gotta pay someone else EVERY TIME.