A lot of vets will charge under twenty dollars to trim a beak, you could also contact some local breeders or bird groomers and see if you can find someone with experience in beak trimming. I would just call the vet and ask them what it would cost, you'd probably be surprised, my vet only charges like ten bucks for beak trims. This isnt something you're really going to be able to correct on your own. Once its trimmed down you can encourage him to chew on cuttlebones and toys to help keep his beak in good shape or it may need to be trimmed at regular intervals, in which case you may want to be taught how to do it yourself if you're comfortable with that. Either way its something you're going to have to learn in person from someone experienced. Beaks have to be trimmed very carefully, if you damage the beak you will have a lot of bigger problems to deal with.
