Essentially it's a work vehicle, paid for by the business and not me as an individual, more cost effective for the business and minimal spendage / liability for me.
You are a sole trader, its your money.
You cut your cloth according to your means, and fortunately for me my means allow me to choose and drive a brand new car
A crap one that you've had to wait 9 months for so far
You speak as if you are some sort of loaded succesful tycoon rather somebody who has decided to setup on his own for the first time.
Seems early days in business to be putting such extravagancies through the books. All your effort should be going back into your business - the first year is critical. After that, then go for it, treat yourself.
You should now be driving a 2 grand POS whilst every spare penny you have goes into your business.
How many other new sold traders flogging used cars have brand new 'company cars'?
You are trying to maintain your previous lifestyle - when you worked for somebody else on somebody elses payroll. Thats gone. You are on your own now. There is a lot more that can go wrong, the buck now stops with you, not your employer. You are your employer.
Your choice, but more new businesses fail than succeed. Mostly due to decisions like this.
But hey, who cares? As long as you can rock up in a '10 plate car and go 'look what I hire from somebody else, I'm loaded' thats all that matters yea?

If you feel a leased diesel TT in white fits your image thats great but I do have to wonder what it is you think your 'image' is.