All personnel employed by the board of commissioners of any utility district incorporated under this chapter, including, but not limited to, the commissioners themselves, are hereby prohibited from receiving any money or other goods or services of value of any sort as a result of any agreement, contractual or otherwise, for the installation of water service within the bounds of the district; and further, such persons are also prohibited from receiving any moneys or other goods or services of value of any sort as a result of any agreement, contractual or otherwise, for the sale of any materials to be installed within the bounds of the district as water service.