you need to get some proper legal advice I'm afraid. get a quote from a few local solicitors first but you are taking on quite a few issues here commercial property, business purchase and transfer of employment for a start. don't try to do it on the cheap or it will all go horribly wrong!
Hi catkin - I am a property lawyer . Happy to help you formally if you want or can give you pointers to look out for but really would echo what others have said that it is a bit risky to do it by yourself. HTH