$400 just to get it tanned?? Wow. Like a rug with lifelike head?
The skull will be pretty easy. Thaw the skull, cut all the meat off you can. Eyes, tongue etc. Once all the meat is off boil in a big pot for about an hour or so. Once that is done make sure all meat is gone, brain included. Their is a product you can get from a hair salon called Basic White. Get this and 40 volume peroxide to whiten the skull. NOT regular bleach. These chemicals will do the skull very nicely. Paint on and leave for 3-4 days then spray off.
Thats the easy quick route. Most taxidermists wont degrease the skull. However, people who professionalize in skulls do. So, after a month or few months if the skull yellows some that is why. If you want a professional job heres how. To degrease after you boil it (before you whiten) you would leave in heated water at 115 degrees with dawn soap for about 3 months. This should remove all the grease and make a perfect white pretty skull and get it to stay that way without degrading the bone.