A-Plan came through once again for me. They came back with AXA as well, but then £71, but has £500 excess. Another insurer, who I promptly forgot the name of (

) came through at £84.99, but with £250 excess (that includes the A-Plan broker fee, I'm with their Van insurance as well so nice to have it all under one roof). That particular policy doesn't actually state that property worked on is covered, but it's also not in their exclusions, Simon from A-Plan called them up and they said it is covered up to £250. But will doubly make sure this is in the fine print!
Pays to call around a bit, not my favourite way to spend part of the afternoon but happy I got it sorted.