I am prep'ing I-134. To support the financial requirements, I am going to have the following documents along with it:

- My last 5 pay stubs
- Employment verification letter from my employer stating salary
- W2 forms for last 3 years
- 1040 forms for last 3 years (I am not including CA540, I guess its relevent...right?)
- Letter from bank about my checking account balance (its quite useless actually, as its meager balance only used for daily expenses etc)

So, the questions I have is:

1. My annual income from my employement is far more then what is mandated on I134, so I am not including all investments, savings, real estate etc, as I feel its of no use. Please confirm my understanding.

2. 1040 forms - all I have are the signed copies of the originals which I had sent to IRS. Are these copies sufficient?
Do I need to notorize these - notorization would not quite make sense, since it would be like - 'its a true copy of the copy'

3. W2 forms - should I send the copies of the W2 forms. I can notorize the copies or do I need to include the originals?

Any thing I have missed out here?

1. You are correct. If you do not need more income then from your employment, there is not need to include anything else.

2. Yes, the copies are ok.

3. Include the orignals of you W2 forms. Anyone disagree?

As a general rule you can always provide copies as a substitute for anything that is not specifically requested to be original. But get always be ready to provide originals of any copy.
And generally for sponsoring:
You can get by on just Federal Income Tax forms, Employment Letter, W2, and current pay stub. The bank statements adds nothing new. I think you might be able to go on less but haven't heard anyone mentioning it on here. That is all we used.
Your local state tax forms are not needed.

I submitted basically the same stuff you listed and had no problems at all.

Submitted all copies, and the only thing notarized was the I-134 and the bank letter (that's because the notary was the teller that typed the letter!).