Something to think about regarding the 2018 is when did the dealer actually receive the unit? Mid to late 2017 or early 2018? How long has it been on the lot? How old are the tires already? I tend to think of how many people and traffic that trailer has already had in it sitting on the lot. How many times the fridge has been opened, the recliners have been opened, the bed raised, the shower opened, etc. and that would make me take pause.
While I realize there is potentially money to be saved and that weighs heavy but at the same time consider the use that trailer has already endured by sitting on the lot that long with every Mom & Pop and 2 or 3 children browsing over it.
Best wishes for whichever unit you purchase and happy camping!