Thanks for all the feedback everyone! A couple more details for clarification and to guide the conversation a little bit more:
1. Class size - Usually no more than 2 (usually a husband and wife couple).
2. Class cost - I'm planning on charging $50, but since these folks don't have their own guns, it's pretty much just to cover ammo and targets. Also, to add just enough "buy in" from the students. Sometimes if something's free, folks don't value it as much.
Do I really need insurance for that level? Could I use a signed waiver instead to help limit liability (Indoor range I worked at used a liability waiver in case some jackleg shot themself.)
Hardware: I'm going to buy another gun. It will have the following purposes:
1. Iron-sighted pistol to teach students (new or non-gun owners, mostly ladies)
2. Potential gateway to get my wife back into carrying
3. Very distant - potential NPE carry gun for myself vs my usual G19 + RMR + XC1
Sort of torn between a G48 or G43. Smaller guns are usually harder to shoot, especially for inexperienced shooters. My thought is that a 19 is probably reasonable comfortable for most, potentially bordering on too large. A 48 seems like the sweet spot, but maybe a little large for most females to conceal. 43 is more concealable, but takes a big hit in capacity and shootability. Yes? G48 is the answer?