'What about selling costs like the broker commission or improvements I made to the house?"
Most home sales end up not being taxable under these new generous rules. However, if you are fortunate enough to have that large of a gain (or unfortunate enough to not have stayed around for two years), you should know that your cost basis in the home is increased by your improvements (why we like you to keep a permanent file on your home), and your sale proceeds are reduced by broker commissions paid and other closing costs.