experiences with building in spain please

Hello,

I have currently bought a house and land in ricote valley, murcia.

I am looking to see if anyone out there has put an extension on their original house and roughly what they paid in architect and licenses?

My husband is a builder so we are planning to do 95% of the work ourselves for which we have estimated an amount for, but know we will need more for licenses and architect fees.

Any advice or personal experiences would be greatfully appreciated 

thanks