Can't understand this non-freedom units to math it, but a few principles to consider:

• Houses are malleable and depreciating assets, not an investment consideration, everything above the minimum is a luxury as long as you have forward ability to modify the structure.
• Land is hard money, no matter what place and time in history you look back to, the difference between serfdom and freedom is being landed.
• Not all land is equal, acreage is not a perfect unit of measure... the waterfront is more scarce than acres of field as it offers its own utility. Also consider flood risk.
• You already narrowed down the structures to something livable, so what piece of land can be made into your families garden of Eden? We all have an innate desire to return to Eden.