Private agreements to contribute to the cost of a water main installation by a subsequent customer are permissible, but the village shall assume no responsibility for the enforcement of any agreements. No property located outside the village limits will be allowed to connect to a water supply main unless otherwise agreed to by the President and Board of Trustees. The foregoing rules shall not apply to contracts or agreements previously entered into by the village which may be in conflict therewith, except as those agreements may hereafter be modified. Nor shall any rules or other provisions of this chapter be construed to imply a grant or right to anyone outside the village limits to connect to the village's water system.