Quick silly question

Okay so i have a 2007 GMC 2500HD Sierra with 6.0. ive installed a cam, bored .30 and ported and polished heads. my buddy has been tuning on it and i?ve recently got into tuning and bought HP Tuners my self. now if i edit his tune just a bit and like later on i decide i want to do a turbo set up or something and i need his help and i want him to do the first tune will he have to buy the credits again to get into my ecm if i tune it with my tuner?

Assuming both tuners are hp, you'll both need to purchase credits to tune the same ecm. Might better have him tune with your tuner and your credits, then you'll have final control over it.

If you both have the mpvi2, you can read and edit. Whoever writes needs the credits. He can tune on his end and send you the file to load.

True, just thought he might want possession of his own credits and tune.