let me preface this with the disclaimer that I am NOT a good builder by any means.... But I would be rather scared to put a nice fancy coil on someones
rda that I didnt know. I hate setting up my firends
rda's. To many variables that I cannot control that could lead to disastrous results. If I put a .15 Stapled Helix on someones RDA and they tried to run it on a mech mod with a trust fire battery and blew their face off that would open me up to possible legal issues. Good luck finding someone to build for you.
That said, its really not hard. just watch a lot of youtube vids and play with your wire. You will pick it up as to how to build them.