check what deals are about. Some lease companies will charge any where up to 18% plus on the interest. Also check on insurance companies. Some will tell you that they will sort it, but dont let them.
most vans will be on a fixed mileage- normally 20,000, and try to get a lease purchase rather than a straight lease. Also find out about the servicing, as most deals quoted will be for van only. All servicing, tax, insurance and all other bills will be extra.
If you still want to go down that route try Ian Hall at swiss leasing, he's about as straight as salesmen come
steve