don't suggest having a trainer come in and do the training, that it should be done by the owner. In your case however, if the only thing holding you back from getting this big guy is the actual obedience training itself, I suggest having a trainer come to the house (do not ship the dog off for training) and do the initial training for you.
Once he gets the basics down, you should be able to take it from there.
He sounds like a big love, and good luck w/your decision. Keep us posted!!