1) Yeah, in cubese, “unsignable” = “you can easily sign this player, but you don’t want to”.
2) You can live mostly on lower D1 recruits, with a few select D2 thrown in. You have to be willing to move off of the good D1 players though. Don’t invest dollars too early. The big key of moving up quickly at lower levels is figuring out how to place these players, how likely better teams will end up going after them, and avoiding *unwinnable* battles.
In California, a private camp could be a good idea. You won’t pull from a bunch of states, so you won’t have a ton of FSS to do. You can’t do 2 separate camps, but you could theoretically invite both D2 and D1 players to your camp. (I would stick to just D1 personally, and scout D2 separately).
Here’s a more detailed description of what I recommend at D3. As noted above, there are other good ways to do it, this one works well for me, and a number of others.