I'll throw in my 2 cents since I did build my trailer from a simple cargo trailer. You can view the thread here. http://www.roadfood.com/Forums/tm.aspx?m=690366
Since you are not capable of building out yourself and since it's too expensive to have one built(which I agree highly with you on) you should buy something like this: http://www.ebay.com/itm/Enclosed-Trailer-Concession-Trailer-85x16-Cargo-concession-HAULMARK-WACO-TEXAS-/321094497112?_trksid=p2054897.l4275
It already has your basics done. You can surely work around the layout even it's not perfect or you could contact the seller and ask if they can install a larger window etc. if it's absolutly something you must have. There comes a point where you have to be willing to make a few sacrifices in order to pursue your dreams. Believe me, I would have loved to have a professionally built trailer built to my specs but it just wasn't in the cards. My trailer is very functional and I like it alot. I was able to build it for my exact purposes.
Do you plan on building the generator into the trailer in a separate room? You'll want an bigger trailer if so. If not where will it be mounted? Where will your propane tanks be? Personally, I would buy a propane generator and get a couple of 100 pound tanks to feed your equipment and your generator.
As far as a general contractor goes, they too are expensive and add costs to your project where you don't need them to be. If you buy a trailer like what I gave you the link to then you can ask for add ons and sub-contract out the hood install and the gas line/ regulator install etc etc. From experience, a sheet metal shop/hvac guy contractor is gonna want like $2-$4K just to install your hood. Things add up quickly. Maybe should pin point a pre done basic trailer like the one above then print some photos and bring to an electrician and ask what he'd charge to tie in your hood. Bring to an hvac guy and ask him how much to install the hood. Ask each trades person in that relative trade what their cost would be to do this and that. keep itemized lists and see where it gets you. In Minnesota a trailer isnt subject to any of the codes a building would be subject to other than health department and electrical so if Cali is the same you can be flexible i guess.
On the wrap you want to have done. You should have a concept in place and be ready to provide alot of direction to the designer otherwise the design itself will cost you thousands. My wife and I brainstormed heavily when we got our wraps done and provided major direction to the designer and I mean MAJOR. We actually sketched the wrap of our truck after the designer came up with the concept for our trailer and the design portion still costed us around $1500 if I remember right. The install was like $2500 on the trailer so that wasn't too bad. But...we got like 6 bids on the install and then choosed between them all. Plus we traveled 150 miles away to get them done. To save money you gotta ask ask ask and ask again.
post edited by kingofcreams - 2014/01/15 08:11:21