All the documents, that are personally belong to you must be original + make their copies as well. Such as
Your birth certificate
Your FRC, make sure you have this, they can delay your visa if you forgot FRC
Your Nikka nama from union council + from Nadra
previous original divorce from union council and nadra,
record and proof of you relationship, pictures, call log, chat whatever you have. (We saved all of call logs on word doc showing our phone numbers.)
All the documents from your US spouse/fiancé, you just need copies, such as their naturalization, their US passport, their previous divorce, their birth certificated from US or Nadra, job letter from their job if he/she is working,
affidavit of support with tax returns. If there is s co-signer, you do need proof of their residency in US, such as copy of their green card or naturalization and their passport and their 3 years tax returns.
If fiancé visa, must have receipt of paid IV fee from local bank.