Andy's,
With many pieces of gear I have worked on, there is a bit of apprehension at taking on something for the first time. Then the apprehension quickly disappears and I get another job done.
Owning your own carwash requires you to fix stuff almost constantly. Changing a
coin mech is one of those things that needs attention. What concerns you about this...the mechanical or electrical?
If you currently have electronic
coin mechs and need to replace them, it's typically the mounting nuts, the return cup and three wires (+24VAC, Gnd &
coin switch)...so not a big deal at all. Have a look at yours and see if its is three wires connected...if there are four, then its a relay type (not likely) and requires a slightly different unit that Magiskist can help you with when ordering.