said by averagedude:I didn't install it (came with the house) but labor is a biggie. Plumbers aint cheap here in jersey.
For reference only Home Depot has:
(all numbers taken from home depot search and I choose the high side of the $)
Water softeners from $325'ish to $450'ish.
Reverse osmosis (large under cabinet systems) for $475'ish.
Whole house incoming filters for $50'ish
Whole house UV filters $400'ish.
So 450+475+50+400= $1,375 for materials cost only (not labor)