[carlsverre]

I'm a fan of this approach. SQLSync effectively is doing this continuously - however it would be possible to coordinate it explicitly, thus enabling that kind of check in/out approach. As for single-owner lock strategies, I think you could also simulate that with SQLSync - although you may not need to depending on the app. If the goal is to "work offline" and then merge when you're ready, SQLSync provides this pattern out of the box. If the goal is only one client can make any changes, then some kind of central lock pattern will need to be used (which you could potentially coordinate via SQLSync).