Our single trip policy provides cover for one trip of up to 365 days. (holidayextras.co.uk)
When finding your multi trip policy, leading travel insurance comparison sites suggest your chosen cover should provide at least # 2 million medical cover and # 1 million personal liability cover. (holidayextras.co.uk)
So you need to ask about a separate trip policy for a load secured to the trailer. (padtinyhouses.com)