The most common difference between my model and that of people I've discussed this with is that many people consider living in a city essential. This is entirely reasonable and I don't expect living outside civilization to work for everyone, but I suspect the accelerator project will work best near rather than in a city.
The core reason for this is cost. With many people operating on savings and scholarships, lowering cost of accommodation is very valuable, even when you're well below bay area rents. Even if renting a room was was $50/m, reducing it to $25/m means a philanthropist can sponsor twice as many people for the same amount of money (ignoring food).
This is not yet fully investigated, but while some cities are relatively cheap, if you want to buy a space which can scale to 20-50 people in a safe city with all the good parts of civilization, I suspect you need a larger budget than we'll have. An abandoned village (or financially troubled commune) does seem to be within budget.
I'm very interested in finding places in cities for sale which have an acceptable cost while also plausibly fitting enough people in decent conditions, and would welcome research into this. Hotels for sale would be one place to look.