1. It is different from family to family depending on their tax situation, but generally, the AMT sweet spot starts when the income reaches around 450K, and ends around 650K~900k, again, it depends on the family's tax situation. For example, the upper range in CA should be higher than the one in FL since CA has much higher state tax.
2. What happens when one person enters the sweet spot?
Basically, he will pay max EFFECTIVE 28% Federal tax only during that range. Compare to the current 35% max tax rate, that's a 7% saving. So, if one enters this range, in most cases, he/she should max his income to reach the upper limit of this sweet spot to take the tax advantage. How? for example, realize short term capital gain, pay state tax within the year instead of wait for April next year, ...
