Parsons is correct that many do not take care of the trailer like the boat. If not mistaken, I think the trailer came from Magic Tilt and probably has grease fittings on the hubs. If so, you can apply grease. I would also tighten the lug nuts and make sure the tires are at proper inflation or PSI which can be read on the tires. I would also inspect the bolts holding the axle to the trailer frame if not welded. Then take the boat down the road for about 10-20 miles suggesting that the owner use his own vehicle. Usually if the bearings are bad, they will heat up quickly and you will notice it within the first 10-20 miles of towing. You will notice a slight heat but if excessive, then the bearings are bad.
As for the tires, if worn, dry rot, parts torn off, etc, then new tires would be warranted. Make sure the motor is off before transport and I would strongly suggest a tie down on the back. When you put the strap over the boat, cushion it with for example a piece of carpet with the carpet face down on the boat as you are dealing with composites vs. fiberglass. Twist the tie down once or twice from the deck to the trailer which will keep it from flapping in the wind and make sure you do not over tighten it either.
