For the Tropes Jam I released "Working For The Corp". At that point it was literally just text in a powerpoint. As I started to make money on it through sales I hired people to first add additional cards, then do art, then edit, then do layout. I paid for all that with money I made from the game. Each time I had a big update I just uploaded the new file to the page. Totally okay, all the people who have already purchased the game can go back and download the new version if they want to and don't have to pay again.