John @wallfish is the pro here. I did quite a few radon mitigations when I was in the home improvement business. Most homes with a sump pit are fairly easy to do yourself. However, there are some situations where you might want to get a pro involved. Where I live (Maryland) there is no requirement for licensing or permits, at lease when I did it. Because of that fact, a lot of unscrupulous characters like me were putting in radon reduction fans. Test results were always favorable afterwards because of the simplicity of it. Think of radon as steam in your bathroom. Steam you can see, radon you can't. But when you turn on the exhaust fan, it removes the steam. Same idea with radon, only you are removing the radon from under the basement floor or crawlspace, and you are running the "exhaust" fan constantly.