Are you planning to grow your company or eventually increase what you are able to offer your customers?
Without knowing your backround - have you considered subbing out your printing until you can build up enough business to justify buying an even larger printer?
My suggestion (just my $.02) would be to find a company nearby (or one of the Merchant Members here) to do your printing so you can look after your customer for now. Once you get a partner to work with, start pushing more digitally printed vinyl and thinking of ways you can move more towards this route. The opportunities are endless once you start working with with large format prints, there are hundreds of different ways they can be used, probably even with your existing customers without even having to go out and get more new customers.
I bet once you start familiarizing yourself with the potential of digital printing you'll realize that you want at least a 54" printer and cutter or printer/cutter.
I personally think you may not get your money's worth if you were to get something in that price and size range.
We went from 15" Gerber Edge & Gerber plotters to 48" Summa plotter, then 54" Roland print/cut, 64" Roland print/cut and 4'x8'...just to give you an example of how we progress from small format to large format. This if over the span of 6 years.
The benefit of working with a wholesale printer is that you don't carry the overhead of a printer, not to mention stocking inks/media/laminate/parts and the steep learning curve if you've never worked with a digital printer before. (It IS fairly simple to take a file and print it on vinyl - but having it print with proper color accuracy, laminating it and cutting it perfectly does take a bit of practice and experience) One thing I'd suggest is to ensure that this company delivers a quality product (they should be able to suggest suitable materials for the application) and that they deliver on time. Your customers don't necessarily have to know that you're subbing it out - but you need to be able to meet deadlines nonetheless.
Hope that helps.