John,
The best way to maintain your trailer for a long trip is to install bearing buddies on each axle, before you go add 3 or 4 pumps from a grease gun to each one. Not to many as you will blow the seal out the back of the drum. Same on the trip home, don't want a failure and be stuck on the side of the hiway in all the traffic these days. Maintanence to a trailer other than that is simple do the lights work, is there enough fluid in the master break cylinder,Check tire air pressure, than you are good to go, Make sure you have a spare tire and the proper jack just in case you need it.Good luck.