Anything is possible. Uncle Sam would love to get taxes from him. But since he'll be illegal, cousin will not get any credit or any "cookie points" for paying taxes.
As far as applying for a CC and auto loan, that will require a CA driver's license, a social security card number and proof of fixed employment .
Behar Intl. Counsel 619.234.5962 Kindly be advised that the answer above is only general in nature cannot be construed as legal advice, given that not enough facts are known. It is your responsibility to retain a lawyer to analyze the facts specific to your particular situation in order to give you specific advice. Specific answers will require cognizance of all pertinent facts about your case. Any answers offered on Avvo are of a general nature only, and are not meant to create an attorney-client relationship.
Any person, regardless of status, who is working in the US should pay taxes on their income. If later on, your cousin is able to legitimize his status, his not having paid taxes in the past can adversely affect him from an immigration standpoint. That said, it is illegal to work while in the US on a visitor visa and your cousin can face consequences for this.
As to getting credit cards and auto loans I believe that would be difficult given that he doesn't have valid US identification or a social security card...
three different questions. 1. you must pay taxes if you work here, legally or illegally. 2. depends entirely on the bank. Some banks do issue debit and credit cards to individuals without SS or legal status or both. 3. yes, but in all likelihood you will need a cosignatory.
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