Just a few days ago we spent around 9 days at a lake and launched and retrieved our 14 foot aluminum boat with our 24 foot Class C.
The launch was at very shallow angle so we had to back Way, way out into the water to get the rear of trailer and back of the boat deep enough to float and launch the boat ... so far out that the water's edge reached to the driver's door!! This was nerve-racking, to say the least.
For the retrieve I got smart and used a feature of our trailer that we never have. The trailer tilts up starting near the front of the trailer ... just remove a pin and tilt it up so the back end of the trailer and the roller way back there is lowered into the water without backing nearly so far out. Just pull the boat up to the rear-most roller and then wrench it onto the trailer with the regular crank and strap. As you wrench, the boat moving forward with it's weight slowly and gently tips the tilted up trailer back down into place so you can replace the pin ... a piece of cake move that then allowed the motorhome to be a LOT LESS out into the water.
I would definitely recommend using a tilt-up trailer to make your launching and retrieving a whole, whole lot easier.