(sorry for this post being a bit rambly, I'm Pre-Coffee)
If you have some time before you're going to get started, there are things you can do today to dramatically cut your feed bill.
Since you have some space, I'd suggest planting some trees for fodder. Rabbits can do fairly well (not as well as on a mixed diet, mind you, but they'll do OK) on a diet of 100% mulberry leaves, so if you plant a few rows of mulberry now, you'll have a good supply of them later. Your profile just says California so I'm not sure what climate zone you're in, but you could also probably grow some hybrid poplars (just no black poplars, they'll kill the rabbits) and some willows on the lower parts of your land, and some apple trees.
That'll supplement your feed, if not replace your commercial feed, for most of the growing season and drop your costs considerably.
You might also want to find the nearest SCORE office, they're a group that gets retired executives and they'll go over your business plan with you, and tighten it up, as well as possibly help you find grants.
You will make more money if you sell direct to restaurants, and in California there are areas where there's not enough supply right now. If you are serious, I'd also suggest contacting some of the reptile clubs (dead on the wire and cull kits can be sold as snake food), raw dog feeders, and heck, these days I'd go to the local Crossfit gyms that suggest people follow a paleo diet and see if I can't arrange group buys of organic rabbit meat. Successful agricultural operations need diversified income. See if there's a local-to-you primitive skills group that will buy your furs, or a local boy scout group. There are workshops being held right now for $100 a head to teach suburbanites how to kill their own food, do you have the space to set up for a workshop like that, walk people through dressing out their own animals? You could partner with someone else who has rabbits to supply them for the workshop and use that money to build your cages. Do you have the marketing skills to pull that off, or could you spend the next year learning those skills?
Breeding stock- you can sell high quality rabbits. This will probably require you to go to a few shows to get some champion bunnies to up your price and create demand, or buy from known lines. Do you have connections with the 4H/Future Farmers crowd for producing meat pens? Now would be the time to start making those connections.
There are also grants available from the Slow Food guys, and lots of agricultural grants available if you do something with, say, a heritage breed. Do you want to raise, say, American Chinchillas, Blanc do Hotots, or Silver Foxes?
To raise revenue to build the cages, you can offer a rabbit subscription CSA, where people pay you a certain amount now to get a rabbit a month, or a rabbit a week, at a discount later. That might help with the up front cashflow issues, and you might also be able to piggyback on other CSA's that are in your area. They might be willing to put out a call to their members to raise seed money for you, and handle your distribution at a much, MUCH better return than the large processor will give you. I'd also see if I could find a cowshare group in the area, since those are people that are already paying up-front to get high quality, clean meat.
You've mentioned your son is Autistic. A lot of parents with kids who are not neurotypical are trying to feed them a diet as free from chemicals as they can, since it so dramatically helps some of these kids. Are you a member of any local support groups, or email lists, where you could offer the rabbit meat direct to consumer?
Some cardiologists suggest their heart patients eat rabbit meat. Could you produce a good looking brochure to give to cardiologists about the low cholesterol in rabbits, that they could hand their patients, with your rabbitry's information on it? A REAL, good looking brochure- have a graphic designer tell you if it really looks like crap. I've seen a lot of nearly useless, bad marketing materials out there because the business owner didn't have anyone to tell them it looked bad, or they wouldn't listen. You can get a decent logo for five bucks of Fivver, there's no excuse
Have several paths to revenue. Think of it like prepping- one is none. If all you do is sell to the commercial processors, what would happen to you if they went out of business, or dropped their prices? You'd be over a barrel.
You might want to also plant something to attract people to your location. A few rows of you-pick berries, some fruit trees, heck, some rare garlic varieties,
If you really want to do this, the thing that will make you money isn't the rabbits. It's going to be the rest of the business. There are some books you should read, the E Myth by Gerber is a good starting point. Your local library has lots of books on business, they're going to be worth looking into.
Edit- double post.
