I just bought a 2008 R21EC that came without a trailer. I got an all aluminum, tandem axle trailer with bunks, not rollers. I bought it from Trailer Depot of Sarasota FL, for $3600 all up- taxes fees, etc. I hauled out the boat as the trailer was delivered then brought it back to the dealer where he lifted the boat and adjusted the balance and set up all the bunks and winch.
They did a great job setting it up. I then towed it home to Maine- about 1600 miles, behind my Toyota Tacoma pickup. It was not a fast trip- I ran about 60 with no apparent strain on the truck.