there are several guys out there that do good work, several that do crappy work that a lot of people think is good, and a few artists that do exceptional work. he should talk to several, find out if he uses the quicktan and mounts the hides on wet, or what kind of tannign process he uses. has he competed and won any competitions? and look at mounts they've done. some people aren't picky and just want a deer on the wall. some are extremely picky and look for very specific things in their deer and will pay for someone to go the extra mile.
i read accuratereloading.com a lot and there is a taxidermy thread on there. i asked some things to look for when searching for a new taxidermist and here is a list i was given by a professional tax.
As a NON-TAXIDERMIST, you need to look only as far as the face of your animal.
(1) Does it "follow you around the room?" Then the eyes are not set properly and likely are cheap eyes to begin with.
(2)From underneath (you high ceiling guys) can you see under the lips or under the eyelids? First indication of poor taxidermy work. The hide has pulled as it's dried. It either wasn't glued properly or wasn't monitored closely enough while it dried.
(3) When you look at your mount from the muzzle straight on, are the nostrils, eyes, and ear butts in a rough straight line with each other? If not, the ear butts are placed improperly. Some may not even HAVE ear butts, but they should all align as an indicator.
(4) Grasp the ears between your index finger and your thumb. Are they less than 1/4 inch thick? If they are greater than that, the ear has likely "drummed". That means that the skin wasn't properly glued to an earliner or that the material used to fill the ear has disbonded for some reason. Do you feel lumps and bumps under the skin of the ear? Likely the ear was "Bondoed" to serve as an earliner and the Bondo wasn't smoothed out properly.
(5) Is the hair groomed and clean? Does the mount "smell"? Another sign of shoddy work. A good mount will have a mild lanolin or leather odor or no odor at all. You should never find dried ticks or lice under the hair. Any putrid smell means that the hide was not properly prepared and that meat has been left under the skin someplace. If the antlers/horns have blood on them, that means they weren't washed properly before mounting. Another bad sign.
(6) Can you see up inside the nostrils? In olden days, we simply filled the nostrils (and "tearducts") with embalming wax. That's totally unacceptable today. The nose as well as any lacrymal glands should have some "depth" of definition there. Anything else is poor workmanship.
(7) On lifesized work, is there a smooth transition of the body, are the legs and leg muscles defined and MOST IMPORTANTLY, is there a smooth and logical transition of the leg to the hoof/foot of the animal. Wrinkles as signs of poor work (Much African work has wrinkles because of a combination of natural appearance and the lack of stretch in African game leather, but that's different.) If you have a wrinkle between the ankle and the foot, it means the taxidmist didn't mount it properly or he tightened the bolts down too tight which "scrunched" the legs up. Delicate hoofed animals like the pronghorn and whitetail are especially susceptible to this mistake. Look for it.