I can't speak for all PoS coins but with Spectre coin:

1. You need some sort of balance over zero and stake for at least 8 hours. The more you stake will get you paid more often. E.g. 100 coins would pay out roughly 1 a month where as 1500 coin would pay twice a week. Daily payments start at around 5000 coins.

2. Payment time depends on the maturity of your coin. Maturity comes from staking it for so long. The higher your maturity, the more likely your coins will sign the new block and receive the reward. More coins give you more levels of maturity.

3/4. With xspec, the payment comes from newly minted coins, equal to 5% of the total supply annually. This 5% is divided amongst those who staked based on maturity and the amount staked, which can give you much over 5% of your stake because not everyone stakes their coins, even tho they still count towards the total supply. You cannot receive less than 5%.

5. No, staking is a means of account for some of the inflation, it does not end. At least with xspec.

6. 5%+ annually. Your daily reward can vary greatly, best to take a average over a long period of time.

Again these answers are just for xspec, but hopefully it gives you somewhat of an idea of how/what PoS is.

Thanks for that detailed answer. I really appreciate it.