Protections from what? People who want to stay in their homes? Who don't want to sell their property?
If the business developer wants protections, they should protect themselves. Don't invest millions in a project that requires the purchase of certain land unless you are damn sure you'll be able to purchase that land.
OR they can appeal to the State, which may or may not have laws and a constitutional system in place regulating eminent domain and attempt to seize/purchase the land legally. Then in court the old lady can explain why she needs 2 million dollars instead of one million, or why her sentimental love of that land is greater than the need to redevelop a slum.