I am in agreement with Pgats that you are still not providing sufficient information to determine his type. What you are providing are mere job related scenarios that could have created a superficial type based on your erroneous understanding of ISTP. Dedication to work does not define any type that enjoys what they do. Why does he enjoy this type of work is it because he allows him freedom to come and go, is it because he enjoys being of service, could it be that he enjoys the problem solving.
I would think that an ENTJ would be about building a one man or small operation into a large company then selling it and finding another venture. I am not sure why you picked the two types exclusively, but if you are considering ISTP merely for his choice of work then the job does not determine the man. He could be ESTP or any introverted type. Does he have a large number of acquaintances?
Sorry, I feel it difficult to provide people with detailed information, but I still want to answer my question so, I will try:
Dedication to work does not define any type that enjoys what they do. Why does he enjoy this type of work is it because he allows him freedom to come and go, is it because he enjoys being of service, could it be that he enjoys the problem solving.
He absolutely enjoys his work yes. It's the atmosphere you have there under the craftsman he likes. They are all a great buddymanship with their on pervert sense of humor

. He loves the job and he is a perfectionist, what be builds will work, you can bet on that.
I would think that an ENTJ would be about building a one man or small operation into a large company then selling it and finding another venture.
Yes and he is mostly into when it comes to finances. He made some money with financial dealings. He is a master of transfering liquids from one account to the other and he often implies that would have loved to study economics. Sometimes thought of him as an ISTJ, but this would be again confirmation biased.
He mainly talks about money, not details of his work. So compared with a typical mechanic for example, he is more to be the atypical one. The storehouse of information he has about his work related things, he never presents to the outside. In recent times he confronted me with new inventions in his sector and gave me insight into technical data. I guess that's because I am an engineer now. But before that, he never did that.
Money though was always a huge issue in my whole childhood. Very sadly that it were so, but I developed freely and wasnt bothered by it to a harmful extent, so its ok.
He always says, if there would be someone, who would buy his company for enough money, he will sign the contract and sell it. So this is another indicator in the ENTJ direction to me.
He has problems to get new customers at the moment and even though his company is not in danger, he constantly complains about it. He could run this way securely for the next 10 years and then goes to retirement, having left enough money. But instead he looks for new ways to find customers, invests in new talents, he fears the lack of wealth more than to see that he is absolutely caught in his wake. And even he is a century away from loosing his company, he still complains about it, not giving the money he wants. (And that year he make the same money like the last year, only the last 2 months now were bad, but he projects that on everything, "the ship is doomned now"

).
I am not sure why you picked the two types exclusively, but if you are considering ISTP merely for his choice of work then the job does not determine the man.
Yes I am sorry. I know one guy I would type istp for sure and he is that practical craftsman. No job he really can not do and he pays proud in it. They are not all this way, I know, I just know to few of them yet. So I tend to misjudge that's true.
He could be ESTP or any introverted type. Does he have a large number of acquaintances?
Of ESTP's I again really do now nothing and I even cant picture them in my mind. So I guess, the answer is: I dont know.