Need "on call" RV maintenance/troubleshooting person (Rio Rancho)

Mobile business, with two Class B Mercedes Sprinter Vans (and one more coming), needs an on-call person who specializes in troubleshooting problems with RV systems in Class Bs.
For instance they are outfitted with Batteries, Electric, Heated Water tanks, Inverters, Solar, Outlets that trip, and other mechanical things that the company is having issues troubleshooting from the manufacturer who outfitted the vehicles with industry components and is out of state and doesn't take calls past 3pm our time.
This person should be super mechanically inclined and have RV extensive knowledge.
Willing to pay by hour or per call and must be available in a moment's notice so business has minimal down time.
Hours business operates: 7 days per week 8:00-7:30pm some days.
This person would come to the van in Rio Rancho to troubleshoot Contract position; must pass background and clean MVR