As an IT person who has worked in this field for over 15 years I usually do not charge unrealistic fees, this is a good sign. If they charge over the top fees, forget it-also if they charge too little-reasonable is the way-say $60.00 call out, and $40-50 bucks an hour plus materials. Talk to the prospective IT assistor/engineer and get a feel if they are confident without being cocky, do not try to 'blind you with science' but speak in good english terms.
Avoid braggart tech-speak jockey's, look for maturity of disposition.
Like all service providers, people go back to the good ones, seek out a good reputation.
Good luck.