I have been doing credentialing for years but I do it from start to finish and also provide contract review and fee schedule negotiations so I charge hourly (varies on location, travel, expenses, etc)
I only provide the additional service of contract review because I have a great deal of experience and education in contracts, and I require the provider have an attorney to "sign" off on my reviews. I charge anywhere from $35-$50 per hour, if it's a part of my consulting services it is then built into my consulting rate of $125-$200 per hour.
I don't use software either. Rather I use a good contact data management program and each client has their own database. For each carrier within each database I can retain forms (scanned and fill in), and do pretty much anything a specific software for this could do. Some of those credentialing softwares are pricey and because of all the carrier updates and requirements changing they can be an ongoing cost.
Linda Walker
PMRNC
www.billerswebsite.com