Check around on a few threads here and in the Jango Fett section. Materials for mine cost about $35 or so. You can make one out of either sintra, foamboard, or styrofoam and paper mache for that price. It takes me about 20 hours to do a paper mache one now, but some people who've got my patterns and tried it have taken about that long and others have taken longer. I don't know how long it took for the sintra one, it's been too long ago now. It will depend on your experience how long it takes you, but I firmly believe anyone can make one if they are willing to put the time in. Some people may have gotten the idea this stuff was easy for me...it wasn't. I went through many trials and put a lot of work into figuring out how to do it, and this was before I was really on the internet, so I was pretty much totally on my own. I had to make do with interim versions, and just kept refining how I'd do it. Every pack I make, I improve it in some way the next time. It is work to make one, but it's fun, too. When you don't keep messing up and having to do the same part over and over. I really hate that, and it happens a lot when you're starting out. At least now, there is so much information out there, so many people who are making their own stuff, and so many different ideas to try out.
One cheap, accurate, and very useful way is using foamboard. ?FOr my gauntlets, I used foamboard for the base then covered it in plaster casting material. Soon, I will make a mold from those and sand down all the rough spots from the plaster. THen I'll make a mold of those and have many copies made. Materials (besides molding materials) were about $20-30.