From Rainbow Aviation's website:
"There is only one repairman certificate, but two ratings: The “repairman (light sport) with an Inspection rating” (LSRI) and the “Repairman (light-sport aircraft)—Maintenance rating.” (LSRM) The inspection rating is available by attending a 16 hour, two day repairman course. The maintenance rating is only available by attending a much longer 80-120 hour Repairman course.
Experimental Light Sport Aircraft
As a sport pilot flying an ELSA for pleasure, you only need the 16 hour inspection course. Classes are normally schedule on the weekend and offered across the country Successful completion of the LSA Repairman Inspection course, allows you to apply for an FAA Repairman Certificate for any Experimental Light Sport Aircraft which you own or one you purchase in the future. (Note: this does not apply to Experimental Amateur Built) Once the aircraft is listed on your repairman certificate, you are allowed to do the condition inspection each year. You do not have to be the builder. You simply have to have successfully completed the 16 hour training course for LSA Repairman Inspection in the assigned “class” of the selected course (airplane, weight shift, powered parachute, glider, gyroplane, or lighter-than-air). There is no expiration date on the certificate of course completion. You do not need to currently own an ELSA."
This says nothing about having to build the plane or any portion of the plane. 16 hour course to do your own inspections, 120 hour repairman course (three weeks) to perform repairs for yourself and others including for hire (LSA only - not GA).
Unless I'm interpreting incorrectly somehow?