Go to Adam Grenier at Sport Thoma in Lincoln NH. It's on the other side of NH from North Conway.. Call first to make an appointment. He's the first and only bootfitter that got my boots right. He explains things carefully, evaluates your foot in depth, and takes a request for a performance fit seriously. Before finding Adam, I went to Richelson's, Roger's, The son of the owner fit me, can't remember his name), Stan and Dan's (Dan fit me once, as did Tink when he worked there; I bought two boots from them), and Bill Haight over in Vermont. I bought new boots from each of these people and had them fit and tweak them for me. All these boots ended up discarded after a season. Lots of seasons and $$ down the drain. But these guys get high recommendations consistently. I believe they are good bootfitters, just not for me. My feet are weird.
Adam grew up training as a racer. Then he coached race kids. He has instructed in the past and is a certified Level III instructor by PSIA. That's the highest cert level before going into examiner territory. At this point in his career he has made bootfitting his professional choice. He's a certified pedorthist, and he makes his own tools when the right one for the job can't be bought. He knows what he's doing.
Sport Thoma in Lincoln has a race room. Adam does the racer's boot fitting at the start of the season, then he works mostly with recreational skiers and the occasional racer. What a racer needs for a good performance fit can be a demanding challenge and Adam is the right guy to do this. He used these skills for recreational skiers.
I highly recommend him to anybody in the area. Call to make an appointment before going. Take your old boots, take your ski socks, and wear pants that you can roll up above your knees. Be ready to spend a couple of hours if necessary.
The shop is a good one too, and it carries a large selection of boots.
https://www.sportthoma.com