It took a bit of digging to find the exact industries that Google offers the Guarantee Service Ads for.

“At this time, Local Services ads are available only for certain service categories and areas.

To see if Local Services is available in your area, check your business eligibility on the signup page.

United States

Locksmiths, plumbers, electricians, HVAC, carpet cleaners, house cleaners, and garage door services.

United Kingdom

Locksmiths and plumbers.”

Source – https://support.google.com/adwords/answer/6224841