So I make $33,200 a year "single" which would put me in the capital gains tax rate for short-term investments at 12% and long-term investments capital gain tax rate at 0%

Yes, there is a limit. No, it does not mean you wouldn't be taxed on the long-term capital gains.

The tax bracket for calculating the tax on a long-term capital gain depends on your total taxable income, including the capital gain. The long-term capital gain is "stacked" on top of your taxable ordinary income. The gain will not all be taxed at the same rate because it will span several tax brackets. Only the portion of the gain that fits into the 0% long-term bracket will be taxed at 0%. With very large gains like you are talking about, a substantial amount of the gain is going to be in the 20% long-term bracket, even if you only sell one of the homes this year.

If you sell one or both houses, $33,200 will not be your only income for the year. The gain on the house or houses is income, too. And it is all taken into consideration in determining your tax bracket.

The only small wrinkle that works in your favor that you did not consider is that the tax brackets apply to your taxable income, not your gross income. So you get to subtract your standard deduction ($12,000 for single under 65) or itemized deductions, and adjustments, if you have any, before applying the tax brackets.

The limit on long-term gains that can be taxed at 0% is $38,600, minus your taxable ordinary income. For example, your ordinary income of $33,200 minus the $12,000 standard deduction is $21,200. That leaves $17,400 ($38,600 - $21,200) of long-term gains that will be taxed at 0%. Any long-term gain above $17,400 will be taxed at 15%, and then 20% for the amount over $425,800.