First of all, one of the reasons that this trailer has an appeal to me is for many reasons.
1. Price - $200 is less than half the cost of a 5x8 trailer kit online, and it's 6x12 to boot meaning that I can extend my current plans to a 10 foot version and still have room for a jockey box and a bike rack.
2. History - The backstory is too long to post here but it was purchased new in 1994 and has been used only 6 times Each time it drove less than 400 miles round trip. The short story is that he left the trailer at my mother-in-law's house and never used it for the past 8 years. It's been sitting there unopened for all that time which allowed the canvas to dryrot, which let in moisture which rotted the floors and allowed mold and mildew to contaminate the bedding.
But! The trailer frame itself in in prime condition. From what I can see by crawling under it, there is no rust nor is there any areas that the powder coat has failed. There may be some spots between the moist, rotted wood and the frame, but that can be sanded, primed and repainted with a few cans of Rustoleum.
3. Salvage and Savings- The unit has a stainless steel sink that I can salvage and use for the under the hatch kitchenette I've designed (and is a popular option for these teardrops). The worst case is that I need to clean it.
It also has a stove that was designed to be moved from inside the popup to outside the popup and attach to a rail on the side of the camper. Again this is something I can clean and salvage and would be more powerful than the $30 Coleman camp stoves and cheaper than the nicer folding camp stoves.
It also came with a propane heater. Now this is going to be overkill for the teardrop (I plan on using a electric ceramic heater with the cool sides and the anti-tip safety features) but since it has never been used (all trips were made in the summer) I can pull that sucker out and sell it on eBay as "Not new but never used" condition. That's money that can be used to subsidise the wood for the construction.
The two Propane tanks it comes with are the newer ones (they were replaced in 2003 when they could no longer be filled without the new valve design). Since I only have a charcoal grill at home, I have no tanks. To go to Blue Rhino and get two full tanks is $45 each ($90 for the pair) or I can buy two new, unfilled tanks for $60 and spend an additional $36 ($96 total) to get them filled.
Or I can take the two that came with the trailer and fill them for $36 and have done.
So...factoring that all together, you can see WHY this trailer has appeal. For $200 I'm a fair sight further ahead in the game than I would be if I spent $450 for the trailer kit, buy a sink basin and faucet, buy a stove, buy propane tanks.
So going back to my original question...Would the Maine registration plan work or should I offer to pay the extra $15 ($215 total) so he can get the title with no money out of his own pocket?
If he can't/won't get the title for me or can't title it out of state, I had already planned on calling this a lost cause and moving along to other options like seeing if I can find another dying popup or travel trailer. I wasn't expecting the Spanish Inquisition regarding a relatively simple question.

“There are worlds out there where the sky is burning, where the sea's asleep and the rivers dream, people made of smoke and cities made of song. Somewhere there's danger, somewhere there's injustice and somewhere else the tea is getting cold. Come on, Ace, we've got work to do.” - Sylvester McCoy as the Seventh Doctor.