How big of a farm should a person buy?

Here’s the problem detail:  I live in Hamilton County Indiana where there is a lot of flat farmland.  In our county, land sells for $10,000 per acre and there are many parcels of 10 to 20 acres available.  I can’t move out of Hamilton County because we own a small business.  (Our business model was valid before the Revolutionary War, so it will still be a good business after TSHTF).

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