I'm trying really hard to figure out the answer without paying $90 to see how TurboTax(TT) is filling out the forms differently than I am. It's a huge deal because I calculate we owe ~$6,500 in AMT this year while TT says we owe no AMT.
Just over half of our income this year comes from long-term capital gains(LTCG) via the sale of business property. I created a single member LLC (sole proprietorship in the IRS' eyes) a few years ago and bought some land. We sold it to a developer this year for a LTCG of ~$113,000. All our other income combined (W-2, Interest, Dividends, Rental Real Estate, and Business Loss) totals ~$87,000. Altogether, our AGI is ~$198,000 after subtracting some HSA contributions. After deductions and exemptions we're at ~$169,000 for Taxable Income (Box 43, Form 1040).
The standard tax computation on our Taxable Income comes to ~$23,300. When I fill out Form 6251 for AMT, it gives me a figure of ~$30,000 for minimum tax. I cannot figure out for the life of me how TurboTax is showing us avoiding AMT. This doesn't seem like an extremely bizarre situation that would expose a bug in their software. The only possibility that stands out in my mind is Line 17 on Form 6251 - "Disposition of Property." The instructions for for Line 17 specifically call out capital gains income from Form 4797, which I fill out for the sale of business property, but sadly I can't find any information about how to refill out Form 4797 for AMT. There's no mention of AMT in the Form 4797 instructions and there's no AMT version of Form 4797 that I can find. Unless that recalulation somehow makes a hundred thousand dollar capital gain reset to zero for AMT purposes, I just can't see where TurboTax is right. Yet it's spot on for everything else I've thrown at it, including two state tax returns.
I'm doubtful I'll get an answer here but I figured I'd give it a shot before I throw in the towel and pay the $90. I can't not do that if I'd wrong and pay thousands more than I should have. Worst case scenario I pay $90 and find out I'm right, in which case I figure I might be able to get TurboTax to drop the fee if there is a bug in their software.
