A used Jet Ski trailer is a good starting point and then fine tune it from there. Mine was $50 off of Facebook, the wife spotted it and it was mine in short order. Bearings is just preventive care and a good idea. Set up lights on something to be strapped down and put in the truck when launched, instead of submerged every time and they will last a very long time. I have a set done like this that are 14 yrs old now and still not hurt.