I did a band share once, but all money came from the band kitty. We were a 4 piece band, and we paid a 5th share to the band kitty. Since we were working regularly, the kitty got to be pretty strong. We used it for band expenses (gas for out of town gigs, postcards, posters, etc), sundry items like a hand truck or extension cords, or for emergencies like pay phone calls, parking tickets, etc.. Once the kitty got to over $1K, we used it to purchase a PA. When the band broke up, the guitarist purchased the PA from the rest of us at a depreciated value. The kitty was split up 4 ways, and I got to keep the hand truck. The previous drummer in the band didn't get anything from the kitty, but the guy who was around at the end did. It wound up being equitable since we got the most work with the new drummer. It went about as smooth as it could, but we were all friends before we put the band together.
Even though I had a good experience, there's no way I would do that again. The band I mentioned was around for about 4 years, which is an eternity in band years. We were young, and we were good friends. Nowadays, bands are much more fluid, so there's no way I could count on folks sticking around to make the final payment. I'm not sure if I can put financial trust into someone I met on Craigslist. I've narrowly escaped some 'joint-ownership' plots in the past that would have thinned the wallet with no hope of a return. At this point, it's just easier for one person to own the equipment and make arrangements from there. I guess as I get older and have more personal financial stability, the need and desire to pool resources is reduced and experience tells me that it's often not worth it. Quite honestly, whenever I hear "we need you to pitch in for XXX", I cringe and and subconsciously administer the smell test