With cutting your own hair, practice makes perfect. Although you wouldn't get it quite right, for a bit of time especially the image you have in your head of what you want to go for and the actual cutting or shaving, never really goes together.
I know this due to my earlier army career days as I wanted to save money, and so with a pair of clippers in hand, I tried to cut my own hair, but always so happens I had to just shave all of it off because of lopsidedness and well never a good way to cut all the different angles as my hair grows wild mostly.
Have you tried the more name brand shops such as super cuts, or great clips, etc... I know they would never be on par with a true barber shop, but they would probably have the same discrimination clauses as does drug stores and such.
Maybe even your best bet would be instead of doing a walk in to any place, you could call in advance and set up your appointment with your name, and then go as such.
Kate <3
Always remember to smile your face