We have purchased two trailers almost entirely online. With the first one, we found the trailer we liked at a local dealer but couldn't make an acceptable deal with them. So, we went home and started looking online for the trailer and ended up making a deal entirely by e-mail for one at a small dealership about 4 hours away. Never even met the salesperson until we got there to pick it up.
With the second one, we found a trailer we liked that met all of our specifications, but it was a pretty new model and not many dealers had it on their lots yet. So, again we shopped online, were working seriously with about three different dealers in three different states, and finally got a good deal (including an above-retail trade in deal on that first trailer AND upgraded tires) with a small, independent dealer that was in another state but about 3 and a half hours from home. He didn't even have the trailer yet; he had to go get it for us from Indiana because it had just come off the line. We never even saw the trailer until we went to pick it up.
Both dealers have been very good to work with on service issues after the sale. The first one even traveled to meet us half-way to fix a warranty issue once and another time actually came to our storage location to fix a recall issue. We had to take the second one back to the dealer to fix a slide that was off kilter a little, but we made it into a camping weekend so no big deal. We were in and out of the shop within a couple of hours and the dealer even showed us how to fix it ourselves if it happened again. We also needed a small part for the refrigerator but he didn't have it in stock. So he showed us how to install it, then ordered the part and sent it to our home. And he is always available for consult if we have questions about anything.
Online shopping has been a good deal for us.