If you want durable outdoor signage your budget is not near big enough.
There are basically two types of wide format machines.
1. Aqueous based inkjets printers
2. Solvent based printers
Aqueous printers use a water based ink that needs a special coating on the paper to bond correctly. You can also print on a basic uncoated sheet of bond paper but coated papers designed for inkjet work the best. These type of printers are often used for temporary posters, indoor banners, proofing devices, and larger photo prints. We currently use a Canon iPF8000 that generates fantastic quality prints...color is almost always dead on too. There are a number of other brands as well that work great, Epson being a good one as well. Keep in mind that while these are not necessarily designed to produce outdoor signage we have been successful using scrim banner material designed for aqueous inks (tyvek works well too) and for outdoor posters that we always laminate. There are a large number of media options, many of which claim to be "water-resistant" which is true but these will generally only look good for a several months outdoors. Since they use specially coated papers to obtain the best results the media is much more expensive than that used for Solvent printers and is easy to scuff requiring either hot film laminate or liquid laminate such as "clearshield". They are also much less expensive than Solvent printers and you might be able to get something very nice if you compromise on the width of the printer. Depending on media type these will be virtually dry coming off the printer and can be finished almost immediately. Based on your budget this is probably the type of machine to get. You will be limited to what you can produce that will be able to go outdoors for any length of time.
The solvent printers produce very durable scratch resistant signage that typically used for outdoor applications such as banners, vehicle graphics etc. They print on uncoated (don't have a special coating for the ink to adhere to) materials and essentially "etch" the surface of the material to bond securely to the substrate. For a decent size machine (54" width) you are in the neighborhood of $20000 (USD) for an entry level machine (look for brands such as Mimaki, Mutoh, Epson (GS6000 only), Roland). For the best durability outdoors you will also need a cold laminator to apply laminate to the prints ($10,000) Seal, GBC, Royal Sovereign make machines that work well for this type of market. If you want to get in the vehicle graphics market you will also need a "plotter" which cuts vinyl and other substrates in custom patterns (such as cutting out some text). The media for this type of printer is generally less expensive. True solvent printers will also need to be ventilated since they out-gas harmful VOCs. There are a number of newer "Eco-Solvent" printers out now that release less harmful VOCs and work nearly as well as the Solvent inks. Prints off the printer will be slightly tacky to the touch but will feel dry after an hour...
we usually wait 5-6 hrs for them to out-gas before finishing and the manufacturer recommends a full 24 hours before laminating. Print quality is not nearly as good as prints on an aqueous printer. Our aqueous printer at 600 dpi print resolution produces photographic quality work that our customers cannot distinguish from a silver halide print. Even printing at 1440 dpi on our solvent printer produces prints that are good, great for outdoor and signage you will look at from more than a foot away but not near as nice.
As noted previously any printer you decide on needs to be paired with a RIP (either software or hardware) to get the best prints from the machine you choose. This allows you to use the correct profiles for the different media types you plan on printing. Without the right profile your print will look like crap as the printer will lay down too much or too little ink for the substrate.
