If you are using the word costs as a noun, then it is plural. You would say the costs are..., never the costs is.... If you are using it as a verb, then it refers to a singular object: It costs a lot of money They cost a lot of money.
The average solar water heating system can cost between $6,300 and $7,200 depending on the tank size and need.We help to make getting a solar water heating system installed in your home both easy and affordable.We provide two rebates to help you offset costs:he Cost of a Solar Water Heating System. The average solar water heating system can cost between $6,300 and $7,200 depending on the tank size and need. We help to make getting a solar water heating system installed in your home both easy and affordable. We provide two rebates to help you offset costs:
1 Electric water heaters typically cost less than gas units but are more expensive to operate. 2  Solar water heaters cost $1,000-$5,000 or more, with installation usually included in the purchase price. 3  A central, whole-house, gas tankless water heater can cost $800-$3,000 or more, without installation. With all needed parts and labor, hiring a plumber to install a traditional gas water heater costs $300-$3,500 or more, depending on capacity (with 40 or 50 gallons the most common sizes); length of warranty (typically 5-12 years); and the amount of repairs required to meet current building codes.