Either get ready to part with some serious cash or go the diy route,
with a lot of time and effort you can get good results but if your looking for professional levels of cutting and printing on anything larger than a sheet of A4 then it's going to start costing.
Stock rolls of film usually only come in 5ft widths * 100ft length and are a few hundred pounds each. They do come in smaller sizes but can work out more expensive. Computer cut tables cost a few grand and aren't the sort of thing you can just throw down in a garage or spare room. And depending upon who's supplied the software there may be an annual renewal fee or a lot code job fee (pay as you cut type of thing). A cheap system will be more than a few grand.
If you go the route of laser cutting then be prepared to part with amounts of money equivalent to buying a sizeable new car and then some. Plus it's almost impossible to get a commercial laser for home DIY use. (you may get one but for sure you never want your home insurance company to find out). Your policy will go from hundreds to several thousand overnight. And the HSE will turn you house into a lab scene from a SCI-FI film.
For printing your certainly going to need a professional printer. The one we have is an A2 HP model and it cost over £4,000 and drinks ink like oliver reed liked a vodka. There are cheaper ones out there but realistically even a cheap one will be over a £1,000
Either way your looking at thousands of pounds to start with and at that level you've started a business and that's a hole different ball game.
I've seen to a few car shows and there's always a number of stands doing desktop vinyl cutting but the quality isn't that much better than what you could achieve with a steady hand a sharp knife and a bit of patients.
Your best bet I'd guess is create your design and get it printed and cut by a local professional. After all thats what they're there for.