Boarding up a caravan

We are currently arranging to board up a property with numerous outbuildings and a caravan.  Contractors are reluctant to board up a caravan using ply and screws as this would damage the caravan.  Has anyone come across this before and had to secure windows and doors of a caravan. If so could you share how you actually did it.

Thank you.

miscellaneous issues

We had a similar problem in Croydon but with a large Winnebago style american motorhome. The motorhome was constantly squatted by vagabonds and ne're-do-wells  - and was in fact more of a problem than the house it was outside.

After service of relevant notices the appointed WID contractor built a cage of Heras fencing close to and completely enclosing the motorhome. The Heras fencing attached itself to itself and therefore no screw holes were necessary in the motorhome. This contractor is a master at folding Heras fencing for a custom made look.  As a final gesture I believe he also damaged the bolt threads so even an intruder armed with the correct sized spanner would not be able to gain access.