Check tyres for signs of perishing, cracks in sidewalls or unusual bulges. Check rims for buckles and cracks, tighten all wheel nuts and always check tyre pressure.
Make sure the handbrake engages and releases properly. Look for rust or corrosion where the base plate fixes to the drawbar and check the condition of any cables.
Check that the handle and wheel of the Jockey Wheel turns freely. Check clamp/bolt for easy operation and look for rust or stress fractures.
A general service should be performed every 10,000 km or every 12 months, whichever comes first.