Thanks for all the replies. Really my main concern is just liability. I feel like I have a supplier in mind that I've bought a few ebikes from and they have been great to work with, before and after the sale. They were not the cheapest, but still night and day from what it costs to buy domestically.
If I ever did something like this it would be a side thing, like buy 10 of the same bikes and try to sell them locally out of the garage and see how it goes, just on craigslist and maybe a small website. People like buying locally around here and if I just did it as a side thing like that it would be easy to undercut some bigger resellers with better components and still get a bit of a profit, even if there are some minor defects here and there. Heck it would be simple to undercut some sellers even if I had to go in and, on my dime, replace the motors on every single bike. It's nuts what some of the bigger resellers charge for what you get. I won't name names, but some of the bigger "hunting" bike sellers are so overpriced, bikes and accessories and that's kind of what has me wanting to do this. Good bikes, for sure, but for $6000 a pop, I could buy two bikes with better components and that's without and kind of discount for mass production (but, at the cost of customer service). It would be fun to just connect local people to good bikes without ripping them off.
Obviously from a buyer's perspective, I'm a guy in a garage, and not a big reseller, so that's the trade off to get the right customer. Basically someone who knows bikes enough to know what they are getting into and is willing to trade a big name for a guy in a garage who will sell you a considerably cheaper bike with really solid components.