You are in a major metropolitan area that gives you access to unlimited resources. You are however limited by a lack of budget and no fabrication abilities. There is a saying that goes; you want it good, you want it fast, you want it cheap, pick two and call me back. In order to find what you seek at your budget, you will have to be patient. There is a reason why my build is taking years to complete; I don't have a ton of money to throw at it. I do have a shop full of tools that make it possible for me to build what I need. It is still costly to do a custom project. Everything will cost much more to complete than you ever imagine. I see two options. Either you spend all your days scouring craigslist, auction sites, etc to find what you want for the money you have, or save your money until you can afford to buy or have built what you want. I have been building custom vehicles for my whole life so I will give you the best advice you will ever hear. Do it right the first time. Doing something half-azzed the first time and then re-doing it correctly, costs twice as much time and money. That is how projects stall, people either get upside down in hours or money needed to finish. I think you should find a shop that will build a tube frame to your specs that fits your frame rails. You can then figure out a way to construct panels to box it in. Once you have a solid box, you can build out the interior as you go along and money permits. There are countless threads on here with a wealth of information on building from scratch. The key is to start with a solid foundation. Check out this thread, the results are amazing:
http://forum.expeditionportal.com/threads/166831-Aluminum-camper-pod-build-thread
