Letter from bank and meeting income guidelines

[acrossoceans 8]

Hi so DH and I are adjusting his status and going through the application process. During his interview for his visa the officer said my income was low for family of 4 which yea it is but living in america Im sure thats not uncommon lol. Anyways they looked at my bank letter seeing the amount of deposits I have made during the last year and reconsidered. So now we are at this point again for me to fill out the sponsor affidavit yet again and see that I am just at the limit for poverty guidelines. I have a couple questions:

1. Can I provide a bank letter again showing a year of deposits and will that help do you think? Is that okay to have emailed to me and printed since its not required?

2. Application does say I can use his income but we need a letter stating his wages will continue after adjustment has been made. He is an independent business owner like myself (I also work full time) we work for a health company. How does this work? Is it the same as if we were needing to provide a letter from a regular employer? Because in any field there is no guarantee we will continue to receive wages.

3. Off topic a bit. He has been working for company as stated above for almost 2 years but since living in another country no taxes were collected. But now he has a ssn and moved here in July. Will he need to do tax return and is it only from July til end of year or total since he started there even though he was not in the country?? Or if I hae to include him on my tax return same question applies.

Thanks!!!