junkmart

Just find a local acceptance agent and they can validate the documents if you don't want to send off the passport 

No need for the sarcasm from one other respondent. OP asked a simple question with no fishiness at all.
 
The attorney can do more that just sit there. People get nervous and make mistakes. While the attorney cannot answer questions, they can most certainly correct the record at the moment during the interview if the OP makes an honest mistake.
 
They can also stop the interview if they feel the IO is asking inappropriate question or harassing the OP, and ask to speak with a supervising officer.
 
For someone with anxiety issues like myself, the big advantage is having extra support at the interview to calm nerves.
 
I know some may respond "well if you're honest, then you have nothing to be nervous about in the interview." As someone with anxiety,  I get nervous before having dinner with family. Anything can set off anxiety, especially a potential life altering experience like an immigration interview!
 
I hope someone will find this useful.

No need for the sarcasm from one other respondent. OP asked a simple question with no fishiness at all.
 
The attorney can do more that just sit there. People get nervous and make mistakes. While the attorney cannot answer questions, they can most certainly correct the record at the moment during the interview if the OP makes an honest mistake.
 
They can also stop the interview if they feel the IO is asking inappropriate question or harassing the OP, and ask to speak with a supervising officer.
 
For someone with anxiety issues like myself, the big advantage is having extra support at the interview to calm nerves.
 
I know some may respond "well if you're honest, then you have nothing to be nervous about in the interview." As someone with anxiety,  I get nervous before having dinner with family. Anything can set off anxiety, especially a potential life altering experience like an immigration interview!
 
I hope someone will find this useful.

I'm in a similar situation. I'm a USC married to Mexican who has been in the US since August 2018. We married in December. He is considered a US Resident Alien for tax purposes due to the substantial presence test (more that 183 days present in US during 2018).
 
Before coming to the US, he had income and paid taxes in Mexico. We are filing MFJ. Because of filing MFJ, we must include his income from Mexico with my income on like 1 of 1040. This is called "worldwide income." In order to prevent double taxation on his income in Mexico, we are filing form 1116 Foreign Tax Credit. It's a little complicated, but read the instructions thoroughly and you'll figure it out. Form 1116 helps you figure out how much of a credit you can take on your foreign taxes. You are not required to provide any prove of what your foreign income was, or how much foreign taxes you paid, but you should keep these records in the event you are audited.
 
If you don't have any foreign income for 2018, then your situation may be even easier.
 
Here are the forms I will file for 2019.
2018 1040
2018 1040 S 3 (Schedule where you input the credit figured on form 1116)
2018 1116 Foreign Tax Credit
 
Best of luck!