Background:
I am a college student with an income in the 15% tax bracket.
I am looking to cash out some of btc to pay off student loans, invest some into traditional markets and have some extra disposable income.
That amount I want to cash out is around 100k.
Much of the BTC was purchased in 2012-2013, it was moved around a lot but eventually I stored it in a tumblers wallet (stupid, I know). I forgot about it up until last June or so when the btc media hype train started popping up everywhere. I moved it to a paper wallet and havent touched it since.
On to my question:
1) How would I go about paying taxes, Im not explicitly sure how much I paid for per coin or how much I bought at each time, which is necessary for calculating capital gains. I was thinking I could look at the transaction history of the deposit address since it would show the amount sent and the value at that time to give an educated guess but the tumbler generates new deposit address after they are used. Am I allowed to ballpark what I spent on them?
2) I am also a little confused on capital gains. From what o can tell, long term capital gains are taxed in 3 brackets (0%,15%, 20%) that corresponds to your income level. Since I am in the lowest income bracket that implies I pay 0% on my capital gains. But if I sold 100k worth of BTC would that count as income? Because then I would be in the 28% income bracket and have to pay 15% on capital gains. Does that mean I pay double taxes? I get taxed for it as income and taxed for the capital gains? Any help would be appreciated and if you need more information let me know.