“Work to be Done by a Licensed Contractor”
Usually, inspection issues are all about “what”: what is in disrepair; what documentation the Buyer has to substantiate any issues; and what the 
Buyer wants the Seller to do about it (fix it, or lower the selling price).
But “who” can also be relevant — as in, “who is going to do the work?”
If the issue is plumbing or electrical-related, the parties’ discretion may be limited, especially if the work requires a permit.
Then, the only one qualified to do it is a licensed, bonded contractor.
Thankfully, however, many inspection issues can be addressed by a qualified handyman.
Sellers know — or should — that Buyers will be carefully re-inspecting the repair(s) — typically, when they do their walk-thru prior to closing — and 
anything slipshod will at a minimum delay things.
If the Buyer wants things fixed properly, the Seller also has a singular goal: to secure a “hold harmless” clause (or the equivalent) from the Buyer explicitly stating that the issue has been addressed and resolved.
P.S.: In a (somewhat) similar vein, every advice book I’ve ever seen on negotiating stresses the “how.” From my experience, I’d place just as much emphasis on the “when” and “where” (see, “Negotiating Advice“).
