Please be aware that our hull shapes on the Ranger Tugs requires a different shape of trailer bunks and cross members than many boat trailer manufacturers are use to dealing with. We are not the same shape as a Bayliner or Sea Ray cruiser!
The rear trailer cross members need to be low enough in the middle to keep your boat low as measured from the top of the trailer frame. That makes launching and retrieving much easier - especially at shallow ramps.
Understanding axle location to get the tongue weight just right is also very important. For single axle you want tongue weight at 10-15% of boat+trailer gross weight but for tandem axle trailers it should be closer to 6-9% of gross weight. Some trailer mfg. recommend different tongue weight percentages. Be sure to discuss before placing an order!
Ranger Tugs uses EZ Loader trailers for most of their models and EZ Loader should have the hull specs and weight distribution info needed for a R23 trailer in order to build it right. I don't mean that statement to be a recommendation of EZ Loaders over other trailers though....
Highly recommend aluminum for use in salt water. Also recommend electric over hydraulic disc brakes and sealed bearings.