So, your car sits idle (but  hopefully not 
idling) 22 hours a day.  Your car payment and insurance meters, though, run 24/7. Wouldn't it be great if  there were some way to turn that down-time into cold cash?
Turns out,  there just might be, but there's a catch. Actually, there are a 
lot of catches.
Here's the scoop:
Yesterday's McPaper featured a front-page item on "personal  car-sharing:"
"
Seeing a business opportunity in millions of cars  that sit idle at office parking lots or on weekends, several start-up companies  have introduced "peer-to-peer" car-sharing services ... Renters pay typically $5  to $15 an hour for a car in their neighbor's garage or office parking  lot."
It goes like this: Jim's newish Saturn sits in the  parking lot all day, and Bob needs to run some errands out in the 'burbs. Bob  signs up with (for example) Getaround, to which Jim is also subscribed (as a  vehicle provider). Getaround charges Bob $10 an hour for the use of Jim's car,  which it then splits with Jim. Win-win-win.
Or is it?
This 
is a blog about 
insurance, after all, and there are a host of  issues with this seemingly simple and convenient new business model. Unlike a  regular rental car service, Getaround doesn't own the vehicles. And since these  are private passenger automobiles, they're covered by private passenger  automobile insurance. Thanks to my friend 
Bill  M, I was able to score the relevant portions of a typical auto policy  (YMMV):
"
Exclusions:... to any automobile  while used as a public or livery  conveyance." [
emphasis  added]
Now, this doesn't apply to "ride-share" or other  car-pooling arrangements. But the Getaround model isn't a car-pool: you're  renting out your car, and that changes the risk in a myriad of ways.
When  you bought your policy, you agreed to the coverages and exclusions in the  policy, and also to your own (minimal) obligations, one of which is to inform  the carrier of a "
material change" in  the risk. Those of us with teenagers are well-aware of how this works: you can't  just neglect to tell your insurer that your 16 year old son is now driving the  family 
station wagon minivan and expect them to pay up with no  fuss when it gets totaled. Likewise, renting out your car to someone you've  never met (and will probably never even see!) is a dramatic change in the nature  of your insurance policy's risk.
Which then raises all kinds of  issues:
First, let's say that you've already bought insurance, and then  you sign up with Getaround. If you call your agent and tell him, the likelihood  is that the policy's going to be canceled, because you now need a commercial  lines plan.
Let's say you 
don't  call him: what are the odds you're going to be a happy camper when Bob totals  your car into the side of a schoolbus full of elementary students?
Then  there's this: you've now dramatically restricted your ability to shop around for  new coverage. Again, if you 
don't tell  the new carrier, then you've lied on the application (a bad idea, and a felony).  If you 
do disclose it, you're going to  be looking at some 
major premiums for a  commercial policy.
California recently passed (and Oregon is poised to  pass) a law forbidding carriers from dropping drivers who engage in car-sharing.  That seems great on paper, but again, Bill M points out that this will have one  of two outcomes: either carriers will flee the state, or they'll raise 
everyone's premiums to make up for the  increased risk.
At least one of the carshare companies provides liability  coverage to the renters. That's nice, but anyone that thinks that the parents of  the kids in the aforementioned schoolbus 
aren't going to be coming after the car's  owner is definitely inhaling.
In perhaps the stupidest comment I've read  in a long time, Getaround's CEO avers that "
[o]wners' insurance  carriers are not liable for anything that happens during the sharing period.  Consequently, it should be no impact to owners."
Rotsa ruck with  that, Mr Zaid.