Not AP members to the best of my knowledge. Like any transaction, it is always best to view the machine in person or have someone local to inspect the machine. If that is not possible, ask for as many pictures as possible.
Given the fact it is just a project machine, there won't be an active "push" to sell it. No sales pitch - they probably just want to get rid of the machine without any fuss. I guess if the emails are not answered - keep trying, call them or wait until it is finally relisted at a lower price.