Echo_Jay

I believe it may be possible for you to keep your household size at two. If your parents are not depending on you for support, you are technically just living in the house as two different households. 

3 years of tax return is not a requirement. Only the latest one.
 
Pay stubs are also not a requirement, but it does help to prove current income. I only sent 3 months, no RFE.

You either didn't fill out the form correctly, or your didn't send the right documents to prove your income or the required tax documents. 
 
List exactly what you sent so we can troubleshoot your RFE and tell you what you did wrong.
 
Read the instruction for form 864 about the household size. Living in the same house as you doesn't necessarily mean they are included in your household.

Did you submit all supporting documents? Tax returns for past 3 years and pay stubs for last 6 months? Look over your copy and double check you completed it correctly as well as signed it.

You need the NOA1 or NOA2 for AOS
 
https://www.uscis.gov/system/files_force/files/form/i-485instr.pdf

You can try doing the following:
 

They likely have a copy, but they want to see your copy of the NOA2.
 
You will need to produce a hardcopy of the Form I-797 visa petition approval notice (NOA2) for your beneficiary's use at the interview (unless the Phils. have some other requirement), and you will also need to provide a copy of your NOA2 with your AOS applications submission.
 
Do not lose it, make several copies. To get a replacement from USCIS costs in excess of USD$400.
 
Good luck on your immigration journey.

No, not needed at interview 

Yep all 3 most recent Year

For our CR-1 interview we were specially asked for the transcript.  They sent a generic checklist and marked what was required for the interview. 2018 transcript was checked while tax return and W2/1099 were not checked.  They only took the latest transcript.  I had other available if asked...they didn't.  Others may have been burned by not bringing the entire return and only bringing the 1040 and W2.  

What you need is what the consulate wants.  Manila rarely asks for financial support but in the event they do,  one year of tax return or transcript is it.  Transcripts are so much more convenient.   If you send returns your fine.  Did you include w2s?

Are you traveling with an organized group?

Your fiance isn't family yet. So the answer should be no. Like the reply above says. 

The DS-160 when asking if traveling with others, it is referring to others with a visa .. not travel companions in general.      A family with tourist visas .. that is "traveling companions"
 
The K-1 is a most confusing visa ... it waddles and quacks like an immigrant visa through most its process ... yet at its core it is a non-immigrant visa.   Forms like the DS-160 will have questions that don't quite relate, as the K-1 intent is not to "visit the USA" but to immigrate. 
 
In the guide in the link below there is a DS-160 tab and within there is a link to a step-by-step guide for the DS-160.
 
https://www.visaconnection-philippines.com/us-embassy-usem.html

Has your petition been approved?  Keep in mind that the visa will expire 6 months from day 1 of medical so if you are not approved I would reschedule medical to be as close to the interview as possible.  

I was on my period when I did my medical exam 2 weeks ago. I would advise her to wear a tampon just to be sure no blood is included in the urine. Also, there is no visual genital exam being performed nowadays so she shouldn't worry about it.

Old posts many times are not a good source of info as things change.   With St. Luke's in the past couple years they have backed away from having issue with the medical during menstruation ...  no blood in the urine for the testing sample is what is vital .. after that relax.
 
You should jump over to the Philippines forum for your questions relating to the visa process as the visa process varies from country to country
 
https://www.visajourney.com/forums/forum/129-philippines/
 
I will had a few links that may be helpful.
 
https://www.visaconnection-philippines.com/medical---slec.html
 
https://www.visaconnection-philippines.com/us-embassy-usem.html
 
https://www.visaconnection-philippines.com/cfo.html