While I agree it can be realtively easy for handy people, not everyone is that handy when it comes to things like this. And not everyone has the tools and the knowledge to use them in order to solve all their house-maintenace issues. This is where hired help comes in.
Use your buddy if you like and he is handy with this sort of thing. As for liability and your insurance, this is entirely up to your insurance policy. They are not all written the same. For any questions about what your insurance covers, your insurance agent is the only one who could answer that.
I can hook up someones dishwasher without issue.. but I know specifically that my company liabilitiy insurance will not cover doing anything with electrican and plumbing. So I don't do it.
_________________
Professional - Audio - Video - Data - Security - Central Vac -
Insured - Trained - Certifiedhttp://www.phand.ca/