Off road 320 lateral roof moulding uses

Hello, I am in the process of looking at purchasing a specific 5 year old tab off road 320 caravan (UK name), which has the lateral rails (moulding?) on the rear but no spare wheel. The owner for the past 3 years has never used the rails. If I did decide I need a spare wheel here, how would I attach it to the rails, or Is there anything else useful I could attach to these horizontal rails. The vertical rails seem to be more versatile with brackets for metal boxes and bike racks.
Any information is appreciated.