I feel like is a stupid question but I had a hard time figuring it out reading the FAQ. If I join today and pay the 19$, will I pay another 19$ the first of September or do I get 30 days before the next payment hits in?
You get 30 days.
You can pay $19 once and cancel it and continue using UE4 for as long as you want and publish a game just follow the EULA.
Publishing a game entitles Epic 5% royalty fee, sell a game for $10 you pay them $0.50. It’s on the FAQ 10 x .05% = 0.50
is true, but also to add a bit more detail, you only pay royalties on income greater than $3000 per quarter (3 months), so if you make less than that in earnings, there is no royalty at all. And goes for each quarter, so if you remain below $3000 each quarter, you can make $12,000 a year without paying any royalties. See the FAQ for more details. 