USCIS has an excellent website on this topic.
This information covers if immediate relative is inside or outside of the US when I-130 is approved. The only concern is the need to follow the rules as they are when the time arrives. This was more of a cocnern in the early 2000s when it was necessary to tell clients that the rules could change 4 times before the I-130 is approved. Good luck.
Legal disclaimer: The statement above is provided by CC Abbott is based on general assistance and not intended to be a legal opinion because not all the facts are provided. The person requesting information and all others reading the answer should retain an attorney who is permitted by the state bar within the jurisdiction who can examine the complete facts and provide a legal opinion on your case. All information provided in the above answer and other information provided by CC Abbott does not create an attorney/client relationship within any state of Federal law.
You may look at http://travel.state.gov/visa/immigrants/info/info_1339.html. You should consult with an experienced immigration attorney to determine if there are any legal issues to worry about. If you are residing in Spain, you may have issues in meeting the requirements for the Affidavit of Support. Good luck.
For a consultation 714-560-0040. The answer provided is general in nature and because not all facts are known, it should not be construed as legal advice. The answer does not create an attorney/client relationship.
The NVC will require a considerable amount of original or certified documents. The documents my clients generally need the most time compiling are police clearance letters and original birth certificates. You should consult with an experienced immigration attorney who should be able to provide you a comprehensive list during your consultation.
You generally will present updated documentation regarding the bona fides of your marriage at the consulate interview. Only sometimes will I have clients submit this type of documentation with the NVC, where there is a particular issue to address. You will need to show the U.S. citizen meets income guidelines. I mention this because you both currently reside in Spain and there is a requirement that the U.S. citizen must generally have stable U.S. based earnings. There is also a requirement that you have U.S. residence, despite the fact you are in Spain.
Yes, I agree that having an experienced immigration attorney helps if the fee is reasonable. You both are abroad. When a case is delayed due to problems, the tendency is to continue to delay and dig for more problems. Efficient processing and a well-prepared case through to visa issuance helps.