This is just my opinion, others may have had more success.
I would think that if you pay a copy shop to produce the artwork for you, it will not be long before you have spent more on this than you would on a second hand laser printer.
The toner transfer process will take quite a few practice runs (and failures) before you discover how much heat & pressure to apply to achieve an acceptable result. I recently went through this while my workshop processing tanks were frozen solid and I had to work in the mildly heated outhouse with strict instructions to not spill anything or make a mess 