sounds like a good prospect !
what do you do on your walks ?
what kind of control do you have now ?
1. will he stay with you on the walks and can you make him start and STOP barking vigorously on command ?
2. will he fetch a tug and grip it vigorously, bring it back to you and release it when you tell him to release it ?
3. if you let him off lead can you still recall him when he is distracted ?
if the answers are yes, he's probably already got what it takes and for many people that would be enough since he's already intimidating and that would prevent most problems before they even become problems
if 1-3 are not solid, get them rock solid first and that shouldn't require a professional PPD
trainer. there are many members here who can walk you thru that part of your training and i would consider it a minimum set you need