Makes sense to me, nothing wrong with cya business. Heck, say a shop builds you a beachin 0.12 ohm dual coil, needing a 40 amp continuous to run it on, least before I'd even try one on

and you take it home and use a 6 amp irc batt. Heck, that ain't the vape stores fault, true he should recommend and sell the correct batts and gear to you, or insure such gear was already in you possession, but to risk my business for a $5 fee, naw, ain't gonna happen.
Truth is, I would never trust a build that I haven't built my self, taken through all the steps for proper firing and wicking, don't even get me started on wicking issues, but haven't found a vape shop yet that can out build what I've learned to do, by being a member of this forum.
If your going to go rba, do the homework, studying and practice, practice and more fraking practice, tweaking and just playing with it till it vape right. The path of the rba is not one to be taken lightly, tis serious business and serious power contained in the palm of the hand. Done correctly, one may get burned a time or 2, but more than likely, will live to build another day. Done wrongly or ill maintained, yeah goodbye Norma Jean, or something like that.