To friends? I don't.
To neighbors? Same deal. I don't ask them for office supplies, they should not expect me to forego the use of the things I use to earn my living.
I'll let my employees use our smaller tools on the weekend, with the understanding that they are on the hook for whatever happens to the eqpt while in their care, whether they're at fault or not.
And quit it with the neighbors already!!

If you want to be in their good graces, give them the names of a few good companies, and offer to give your opinion on the bids and designs when they come in. They will feel much more comfortable with their decision, they will likely still mention your name to other people, and now you don't have the headaches. Oh yeah - and now you get to see how your competition handles bids and designs.
