Local government has the most influence on real estate markets. It affects the supply and cost of real estate through zoning and land use regulations, fees on new land development, and restrictive building codes. It also affects rental rates through the assessment of property taxes. Finally, local government affects the supply and quality of real estate through the provision of community infrastructure and through building codes. The Federal government influences real estate through income tax policy, housing subsidy programs, federal financial reporting requirements, fair housing laws, and disclosure laws. State government generally has the least influence on real estate. State government affects real estate through the licensing of real estate professionals, establishment of statewide building codes, the creation of fair housing and disclosure laws, and through numerous housing related subsides for low and moderate income households. In addition, the state may protect some environmentally sensitive lands from development. A developer may choose to use restrictive covenants to limit the use of the land for environmental purposes, while maintaining the quality, stability, and value of the surrounding lots. Restrictive covenants are strictly private because only parties of interest can enforce the covenant. In the case of an isolated deed restriction, the owner who created the restriction or that owner's heirs are the only persons who can enforce the restriction.
Court decisions frequently follow common law, which holds that property should be used productively, and favor fewer restrictions over the use of land. Whether the restriction is in an isolated deed or part of a general set of subdivision restrictions, the courts have been reluctant to maintain them for an unreasonably long time. Even in states where no time limit exists, courts may refuse to enforce restrictions due to changing neighborhood character, abandonment (neglect of enforcement), and changing public policy. In most states, it is difficult to maintain individual restrictive covenants for more than a few decades, and several states have enacted time limits of 20 years or so.
On the other hand, the developer may choose to use a habitat easement on the property. A habitat easement can limit the use of the land for the specific purpose of protecting the environment. An easement in gross, defined as the right to use land for a specific, limited purpose unrelated to any adjacent parcel, will achieve the developer's objective. The easement can be transferred to another owner without the transfer of a parcel of land. The easement is less likely to "fade away." Courts are more likely to honor and protect the easement than a neglected restrictive covenant.