The worst possible scenario is to buy new and park it in one spot for the season. How will find and fix the problems that every new unit comes with? Buying new is for folks with way too much money, as noted you will eat 30 to 40% the day you drive off the lot. It won't come with much in the way of necessities and sadly most first timers buy the wrong trailer (at least once).
Look at all the pretty new ones and find the floor plan that works for you. Then get on the internet and find a nice 2 or 3 year old lightly used, well equipped (WDH, hoses, chocks tools etc), model for half the price of a bare bones new model. Ignore dry weights as they are pretty much useless. If a salesman quotes you dry weight or dry tongue weight "Run Forrest run! (he is not your friend). Figure 13% of the trailers GVWR to determine real world tongue weight. Keep in mind that TW must be subtracted from your tow vehicles payload.
Most first timers don't have nearly enough tow vehicle so look carefully at what you have and what it can really handle. Be aware that you will probably not be able to tow anywhere near it's rated tow capacity because you will be out of payload long before you reach that
number. As always.... Opinions and YMMV. :C