A couple million dollars a year [1]. It's always interesting to me how relatively little money it takes to make life objectively worse for everyone else in the country while making a small number of people richer. For the cost of a nice house or a low-budget indie film you can make sure taxes are difficult to file for everyone. Of course there's more to the influence these companies have than the dollar value they spend per year but still, it ain't that much money.

[1] https://www.propublica.org/article/filing-taxes-could-be-fre...