We married in Spain, both being Ex pats and there is no quick way about it.
You need to go to your local town hall for a list of what they require you to have - this can vary from region to region, but typically includes:
Translation of birth certificates from whatever language to spanish (all translations must be bonafide ones, done by a legal translator and stamped). Cost varies, I think we paid about 25 euros per document.
Copies of passports
Translations of all previous divorce documents (if applicable)
Certifcate of no impediment (we got this from our British consulate, where we filled out a form and they put the ‘banns’ up publically for 3 weeks, if no one objected then we went back and claimed the certificate, cost about 100 euros)
One of us had to have lived in this town for at least 2 years - registered on the padron, so they checked back on that.
Plus some places may ask for other bits.
Once we had all this they then sent it off, we gave ours in to the town hall in September, and got the ok in February for our April wedding. They all thought we were crazy organising things with no guarantee that the papaerwork would come back ok. I’ve has friends marry who have only got the ok the same week as their weddding. If the papaerwork isn’t right they send it back and you start again,.....
If your fiance hasn’t registered on his local padron, then I think you’ve very little chance….its always worth asking tho.
Good luck