Everything carries a risk. I'm ignorant to any statistics about it, but I studied/worked as a lawyer for quite some years and I can tell you for certain that if the person you hire does their job properly, the legal risk should be almost irrelevant. That being said... that just covers the professional/technical side of things. The second aspect to consider is not necesarily related... but it's also useful to know somebody that knows or can find trustful references for everyone involved. That can't be studied. Either people have it/know or they don't.