Here's how we do it...

I work for dad as an employee and pay him fair custom rates for his equipment.  I also own equipment and he pays me fair custom rates for what I do for him(minus the operator, since he provides the labor).  I have a brother(who is involved) and a sister(who is not) and it is very important to mom and dad that everything is kept equal, which is tough on all ends - but we make it work and everyone is happy at the end of the day.  We did it this way so it is cut and dried, there are no questions on who owes who.  As far as financing, you may need a co-signer for an operating loan.  If ma and pa are amennable, that is great, if not, go the FSA route - but get on your own asap.  Not only does it look good to those you are paying that it is only your name on the check, but it feels damn good to know you don't need someone elses Herbie Hancock to make a decision.  Good luck.  Ben