Who is planning on spending a fortune on Christmas lights this season? I went around to 4 couples and asked, and only 1 said they’ll be going all out on Christmas decor. The rest of them won’t be breaking the bank or their backs on holiday cheer. So on average what will folks spend if lights cost between $55 and $300 depending on the blueprint. At our favorite stores, they range from $5 to the elaborate stands of $20 to $30. The expectation os to use 10 to 30 strands to cover a medium-sized home, costing around 1,000 and 2,000 square feet.