Like New tankless water heater - $400 (Roberts)

I have a Tankless water heater 42k BTU it is a a Girard Intertek On demand tankless 2.
9 gal per minute Constant Outlet temperature The unit has been used for one season.
The reason for my selling it, is due to we wanted a larger tankless unit because of there being four of us and long showers are a must for some.
Lol The unit is compete with wired controller and door, color is black and its dimension is 15"x15".
The unit itself is 12.
5"W 12.
5"H 15.
5"D I am asking $400.
00 for it, but will consider less for a serious buyer.