You came to the right place.
First things first. This plane is out of annual. So I would do a pre-buy, by an objective mechanic. It would pay you to have someone you know look at it. Look most particularly at the engines, props.
Look at the exterior. A good paint job can hide a multitude of sins.
I would suspect that you will have to replace the front engine fairly soon, and the rear engine perhaps as well.
Send me an email, I have some suggestions for you.
ljb@safetyservicesinc.com