MAN I SURE FELT BAD FOR A NEW BCB OWNER

Got a customer in shop few weeks ago with a brand new p4 who had never owned a boat. First trip out him and his neighbor got out in it and while out started seeing water coming in thru drain in floor. They paniced and about 6k in damages later the got it back on trailer. Had to have new rub rail new trolling motor. glass and gel work on front, skeg was all chew up fixed and repainted a big job. Worked our butts off to get it just right and got it finished 2 days ago. He comes to get tells me the story and wishes he had someone to go show him how to run it. Well me and my big mouth offered to help him. So we get out on water I am walking him thru all the switches and such on his boat everything going well. motor idling for 30-40 minutes as we are doing this. Get ready to take off I had to adjust hotfoot for him and such give gas it died. Not normal for an opti. Get it back going go to take off get up and I could feel a slight surge. Ran about a mile 2000-2500 rpms then idled 20 minutes thru idle zone . Got to mouth of pass in Lake Mareapaus and got on plane water was very rough and I showed him the best way to drive thru it and all was ok til we got to smooth water . Acclelerated a little and the surging started worse so stopped to head back to landing it died again. Had no power then would have plenty, it was crazy. First trip out 6k wreck 2nd trip out these motor issues . Super nice gentleman and I felt so bad for him it was unreal. I really felt bad for motor since I was driving his new boat which he was glad I was with him. He said he would have been scared had he been alone. Man I dont know whether to be mad at myself for going and driving his boat or to be glad I was so he didnt get in a bind. So anyway his new boat is back at dealer and I lost a days work in the shop and both of us feel like doodoo