I would say that the fact is 'saving' is singular and 'savings' is plural. This dictates the verb that follows. You could say A saving of $20 is ... or Savings of $20 are ...
A basement bathroom can be built for about $15,200, Fred estimates. Of that, plumbing is the largest component. These prices are based on costs for a small bath measuring about 6 by 8 feet, with 8-foot ceilings. However, many basements are limited to a 7-foot ceiling. Another potential cost-saving location for a new bathroom is the attic.
An addition with a kitchen can run $250 to $300 a square foot, not counting finishing details like appliances and countertops. An addition with a bathroom can cost $125 to $200 a square foot, again with a number of cost variables including type of flooring, shower and tub, plumbing appliances or custom lighting.n addition with a bathroom can cost $125 to $200 a square foot, again with a number of cost variables including type of flooring, shower and tub, plumbing appliances or custom lighting.