Crypto basis or stock basis

[Pacun]

My brother owes me 9K and I withdraw that amount from his account by using my binance.us account to buy 5 Ethereum coins. What is the basis for my Ethereum coins?

Same situation except that my bother gifts me $9K and he has never gifted anything before. What is the basis for my Ethereum coins?

What about if audited, how can I prove the IRS that I have basis on the coins if my bank statements don't show that I have purchased the coins?

[Pacun]

I guess no much interest in crypto despite de fact that the potential of big profits exists for 2023 and EVEN more for 2024.  Read between the lines please and remember that the potential exists. 

[Lee B]

https://www.irs.gov/newsroom/understanding-digital-asset-reporting-and-tax-requirements

[DANRVAN]

8 hours ago, Pacun said:

guess no much interest in crypto

 

I have not had any practical experience, but that is about to change with new client last week.  

[Pacun]

6 hours ago, DANRVAN said:

 

I have not had any practical experience, but that is about to change with new client last week.  

I think you need to treat this as if they bought stock, except that now wash sales. A few items, usually a few bucks are earned or drops and they are ordinary income but they are tiny sometimes.