Invisible007

the form said (for me)
how many are u sponsoring (1)
then list your spouse if married (another 1)
and myself 
and the form back then automatically totaled the amount which was 3 and was only 2

it should be changed as it doesn't make sense (never did)   but USCIS doesn't see the flaw

That is what I would do.  No person should be listed more than once. 

If the I-864 is insufficient at NVC, they will send a checklist request a new, satisfactory I-864 from you and/or a joint sponsor.
If NVC accepts the I-864 but the CO at the embassy refuses the visa, he/she will issue a 221(g) requesting a satisfactory I-864 from you and/or a joint sponsor.
 
Both cases would eventually be fine if you eventually have a satisfactory joint sponsor. It will just delay the case (usually a month or 2 for NVC(?), or anywhere from a week to few months at the embassy level...depending on how quickly they process cases).
My suggestion would be to find a joint sponsor just in case.

Since you are working as an employee now (W-2 worker), they will base your current income on that. They can still consider earnings from past years in the public charge concern decision, but your current income would be documented via your paystub + employment letter.
 
How old are your parents? Will they be working in the US?
The reason I ask is because healthcare costs can be very, very significant. They won't qualify for most aid for at least 5 years from entry. The CO will take this into consideration as well. Being borderline above the minimums has virtually 0 chance of approval if they are not of working age and capability. Even without that, adding assets or using a joint sponsor may be needed to satisfy the CO.

If you are filling for your dad u need to send your parents marriage certificate initially to the uscis with the i130 form.  Later at nvc stage u will be required to send the above mentioned documents photocopies I mentioned before. Then at interview abroad your parents will take the originals with them. 

Yes birth certificates,  marriage certificate and police certificate are required.