visitor visa for parents and in laws together

[itzpritam]

Hi,
I came to USA on 2nd DEC 2006 on H1 B visa and my wife on H4, but because I was on short term, my company paid me as allowance and I did not receive the US paycheck. But on 15th Jan, my stay got extended and i am on US payroll since Jan 15th 2007.

I want to sponsor for my parents and in-laws for visotr visa. My parents have the passport, and my in-laws passport will be ready in 2 weeks.

Would you please help me find the answer of my questions?
1) Can I first sponsor for my parents and then my in-laws separately?
2) Will there be any problem in the Visa for my in laws, if the visa for my parents is already done?
3) I have sent the I-134 form for my parents. While sending it for my in-laws, do I have to mentioned that I have already filled a I-134 for parents in my in-laws I-134?
4) I read that $5000 is enough as bank deposit? I am having the same amount currently in my bank. Is is sufficient for getting the visa done for all 4 of them?
5) As I was on payroll from 15th Jan, i do not have the pay stub for December, so I have currently only 2 months pay stubs. Is it enough?

[immihelp]

1. Yes.
2. No.
3. Yes.
4. yes.
5. Yes.