As it's a once only trip, it would probably be cheaper to pay someone that already is insured for towing to bring it for you. Standard charge is about £1/ mile. Ok that's £84 but short term insurance is likely to cost that much by the time you've paid set up and cancellation insurance.
However, I do endorse all those recommendations for the NFU. Agreed they're not in the business of short term insurance, but as your standard insurers they take some beating. All our family cars and farm machinery are insured with them. All car and tractor policies automatically cover any trailers being towed. In addition, if we want to hire a digger for a few days they just add insurance on to one of our policies for nothing.
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