I filed a similar issue, but I want to narrow the scope to just the ACA tax credit (ignoring the self-employed wrinkles and ACA tax deduction).

Basically, now that you have Roth conversion and 72t, having an ACA tax credit Income type is essential to modeling these scenarios. ACA tax credit is a relatively-large source of income for leanFIRE folks. User just needs to provide a few things: - household size - SLCSP (second-lowest cost silver plan) - actual plan premium (you might even be able to skip this. Basically if the plan chosen is less valuable than the credit, you don’t get the extra money). Another thought: you could integrate the Insurance Premium expense with the Smart ACA tax credit such that you’d enter all 3 pieces of information in one place.

There’s technically a lower bound on incomes that allows folks to qualify for medicare instead of the ACA. That’s an interesting case, but you could probably treat these as the minimum income level for ACA and give the maximum credit based on other inputs.

If you do all of the above, then you’re technically very close to implementing the Self-employment piece as well. Basically, if someone has self-employed income, they would earn a tax deduction for the remainder of the premiums not covered by the tax credit.