Xavier Williams Unisex Hair Salon

Disrespectful old guy, have been coming to this guy ever since i moved to san francisco from so cal, always tip the guy dollar or so,
so today i went over to get A HAIRCUT ($ 15) with xavier williams, i noticed he had a (debit swipe machine to charge his customers and asked him how long he had it, he had mentioned since last week counting from this same day 02÷9÷16, so i assumed he knew how to work it and that it worked) in my haircut process he than started cutting my beard worth extra 5 dollars without asking me, but i didn’t mind paying extra 5, the only trouble in my mind was that i had 17 dollars in pocket, but since i assumed he knew how to work his machine and that it worked i would be able to pay him, once finishing he made me swipe my card twice charging me 20.50 twice = 41 dollars, luckily i checked my card and they didn’t go through… to make it quick, he didn’t know how to work it kept calling people for help. i asked him that i could pay him in money, but that i would need to go to the bank cause i still owed him 3 extra dollars, and that i would leave him my ID to guarantee him i would definitely come back to pay him. he flipped out on me and started cussing «how you going to fucking do me like that, did you fucking come here without thinking on how to pay me» of course i take account that i should of brought more money or told him to stop right when he first touched my beard… however he could of said in a different manner. so i started smiling due to the fact i was in shocked he was flipping out on me and he even had the guts to confront me why i was smiling so i responded because he was being disrespectful, and that i didn’t come to his barbershop with no negative intentions… at this time he had already grabbed the 17 off my hand and wanted to give it back, but i did not accept, after leaving his premises he decided to yell at me not go back, i had good intentions in coming back to pay him the 3 extra dollars, which i did not due to the fact that he would start a fight or just a scandal. I take account that i should of said something or brought more money, but talking to your customers in a rude manner was unacceptable, there are better ways of approaching a situation. I have not called the police to report this but i do write this to in order for evidence. BGM
His a nice guy, but has some anger issues. he has a good price, rate of his cuts is a 7.8 however his clips are very bad, they will literally get stuck under your skin.