Here's another point of view that may ease your mind.
I'll start by saying that I HAVE a Radon Remediation system in my home - (the level was 38pCi/L). I ALWAYS advise my clients that levels over the "minimum" be taken care of. I ALSO HAVE a Continuous Radon Monitor in my home and when my fan was off during some repairs in the basement, I can document my radon levels ranging from 1 pCi/L to 9 pCi/L for the 7 months it was disconnected. The level does fluctuate depending on time of year, weather, temp and numerous other factors etc.)
The systems are pretty inexpensive so I feel they are worth it , and if they give a person piece of mind, all the better..
However, after working with an Industrial Hygenist years ago, he did open my eyes to radon levels, how they are tested, (the flawed "cancer risks" , and "minimum acceptable level from the EPA" etc).
You can do a quick search for "Radon Myths" and dig up some really good info that my ease your mind a bit as well such as the info at this link:
In the end, having a system installed certainly could not hurt and may be a good idea especially if it gives you piece of mind. Since every circumstance is different, it certainly could do no harm.
I'd thought I'd pass that along since I've always been interested in science, radon, previous engineering background etc. There is some interesting info out there.
Good luck with your home, a home purchase is an exciting time in your lives. Don't let a remediation system stop you if the home is otherwise a perfect fit.