At GameStop, buy one select trading card pack, board game, or puzzle, and get a second item of equal or lesser value for free. Choose in-store pickup to dodge the $4.99 shipping fee, or bag free shipping on orders of $35 or more. That's both the best sale we've seen on these items this year, and a very cheap way to stock up on Pokémon cards (for anyone still staying analog in the age of Let's Go). Deal ends December 25.
You don't need to hire a contractor or do extensive renovations to add value to your home.