Hello Aditi
1 ans: Yes, before and after.
2 ans: Yes, payslips are mandatory. But we have options for it.
3 ans: Yes, but we have options for it
4 ans: yes, you can change your status to H4 and travel to home country, if you find an employer who transfer your H1B, then again you start working.
Hope this information is needful
All the best...!!
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