Had it done over 2 years ago so im a little sketchy on the specifics
was just under £400 i think, maybe £360ish
this was a drop out of bike, they send a van and pick them up then 2 weeks later (was a bank holl in the middle of it ) they drop them back all sorted
includes springs rated for your weight/style of riding. comp and rebound etc sorting out (they also replaced a adjuster that had siezed up for me) plus as expected a full service.
they were set up on what they thought would be the best settings given the info i gave them and to be honest i played a little but returned to thier settings as they worked so well.
i have heard lots ot other attempts at sorting forks from coins in the top to dif weight oils or new springs.
if you want to go diy then a new set of Ktec springs (or springs of your choice from where ever) and a service with fresh oil makes a fair diff. Ktec are pretty good at working out the best spring combo with oil to use for you but then so can many other fork guys.