Commissioners of each county are empowered to lay out, build, repair, improve and maintain highways and bridges in any adjoining county whenever it shall appear to the commissioners that the laying out, building, repairing, improving or maintaining of highways and bridges in any adjoining county is or will be in the interest of the particular county or of benefit to the people of it. The expense shall be paid out of the county highway fund of the county whose commissioners order and contract for the work to be done. Any highway or bridge work shall not be done in any adjoining county by a particular county if the work would impair the credit of the adjoining county, injure property, or be detrimental to the interest of its citizens.