Your premiums may cost less if you keep your van in a garage, or a secure off street location overnight.Also what you keep in your van, may also effect your quote.
Every region in the UK is risk assessed by insurance companies, so even if you are a careful van driver you may pay more on your premiums because of where you live.
In some cases if you add a second driver to your policy who has a good driving record it can reduce your insurance costs.
If you are making a claim and have comprehensive coverage most companies try and settle the claim within 5-7 days.