Every caravan or camper will have different needs, depending on the type of chassis, suspension....etc.
Most manafacturers will have a service schedule, much like a car, with service intervals recommend.
We will focus on a standard caravan with leaf spring suspension.
1, First thing is to inspect the chassis, check the welds, nuts and bolts.
2, Remove the bearings and seals and inspect, replace if needed, re-pack the grease. We always replace the seals and replace with new ones.
3, Remove the brake hub and inspect brakes, replace if needed.
4, inspect the hand brack and adjust accordingly
5, inspect the suspension and re-grease as needed.
6, Inspect all drop down legs and lubricate.
7, inspect Coupling & coupling bolts.
After your first service, it is recommended hat you get your caravan or camper serviced every 12 months or 10,000ks.
You could expect to pay $330 for you first service for a single axle caravan or camper plus parts, ie: new bearings. A tandam axle unit will be around the $380 range.