rabmc

As above what the best route to go if your self employed and want a new van , got a van at the moment that i bought out right but looking to upgrade to something bigger in the near future , my vans probably worth around 3.5k-4k id say , but couldn`t afford a bigger one at the moment , would like something new but theres leasing and finane etc , just any info would be great in regards to tax etc with doing the above