Hey there! I just got my approval for my K-1 visa so me and my fiance were just planning the same thing and it sounds like we may have a similar amount of stuff (I have kitchen stuff, a lot of collectibles and games, and 2 books shelves + 2 carts).
Our distance is a LOT shorter than yours (Nova Scotia --> NYC) however what my fiance is doing is renting a cargo van in NYC, driving to Nova Scotia, loading me up and driving back. The reason he's renting it in NYC is that UHaul only rents cargo vans locally (no long distance drop offs) but it STILL ends up being cheaper for us then renting a 10' Uhaul. For your distance however, it may be cheaper to rent the 10' Uhaul and drop it at your final destination.
When you go to cross the border we have seen MANY websites say that you need a full inventory of all of your stuff. What I did when I packed my stuff up (I was staying with family because my lease went up, so the majority of my stuff is already packed and in storage waiting for the move) was write everything that was in the box down in a notebook (like "Hair / Make-up, Over the counter medicine, bathroom shelves, shampoo / body wash -- Bathroom Box #1") and also wrote that on the outside of the box itself. This will apparently really help facilitate a quick border crossing.
Good luck, and I hope your process goes quick!