I'm just chomping at the bit to add my two bits here. I'm from Alberta, Canada, and recently bought my first bucket truck this last Spring from an equipment dealer in West Chester, PA. It, as yours, was supposed to be "work ready". Well, it never made it home. It didn't even make it out of the State before it broke down. I limped it to North Dakota, where I had to have it towed to the border, then towed to Regina, Saskatchewan, where it sat for 3 months while getting the necessary repairs done to make it roadworthy, to the tune of an extra $20k. So, like you, my experience with used equipment sellers stateside is not very good. Seems to be a lack of conscience in our cases...
Anyway, next time, I'm not going to make a non-refundable deposit until I actually see the item in person. In my case, it was a situation where I would have had to walk away from a $5k deposit I made over the phone. Hope you made out ok after...