1. The one they're working on results in a "grocery store" when done - it's coop run and handles working with distributors, etc. It often ends up "feeling" like a Whole Foods or similar, as the "non-direct" farm products end up sourced from similar distributors.
2. The "farmer's market" type - where you end up with basically a continual farmer's market - this one can grow into being more of a "grocery store" but is often quite limited on the products available; think almost entirely local farm produce and nothing much else.
3. The "community supported agriculture" type - where you pay a flat fee and get a box every week/month/whatever, but don't really have much choice what's in the box. These can be the "closest to the farm" as you're literally getting boxes of whatever they're harvesting. However, they're often only active during harvest periods and you don't control what's in them.
The third one is the only one I've seen be consistently higher quality (and if I had to rank them it would go 3,2, 1) because the farmers pick the super ripe stuff for the CSA because they know it will be delivered and eaten in a day, not packed into a truck for travel across the country. You can also end up with strange fruits you've never heard of before, but still exist.