Visible has a family/friends plan - called "Inner Circle" - that comes with a $5/month discount on the Visible+ or Pro plans, and allows one account to pay for all the others.

Ah, cool, looks like they added that about a year ago. I hadn't looked at Visible recently. But Inner Circle just brings Visible+ down to the same price I'm already paying Verizon ($30/mo/line) since it doesn't stack with other promos and doesn't combine with an annual plan. And I'd still have to setup four separate accounts, I could just pay them all in one place.

Still, thanks for pointing it out.