US Immigration from Nicaragua

I am currently filling out the affidavit of support for my K1 visa. I am the US petitioner. My question is, if my income from taxes isn't enough to qualify as a sole sponsor for my fianc .. can I include my savings account in the affidavit?

I was thinking of doing this while also including my mother as a joint sponsor, who technically doesn't make enough either but I figured it could only help my case?

What is the time frame, after filling the N-400 online?

Thanks in advance,

Regards,

OA.

Working on the N-400 for my wife. Over the years she has done a combination of work, some that she received W-2's, paid income tax, etc. and some in what I think of as the "Informal Economy" - such as cleaning houses and offices, work in which she did not receive W2's nor pay any taxes on. She has no documentation for this informal work. In some cases this work was sporadic and in other cases that was really the only work she did for a few months at a time. Over the years covered for the required reporting I estimate it is probably about 50% "formal work with W2's" and 50% informal. My question is how to report this in Part 8 on the n-400 form, such as "Self Employment" or not to even report it at all? Obviously I know how to report the work for which she received W2's.C

I appreciate any advice on this.