Rick Steves. I lived in Europe for two years with the military and have been back several times. We went on a trip in 2019 with our family (five kids) and made our way around the entire country on the type of budget that you’re hoping for. I would not go through a travel agency… I would read Rick Steves Spain travel book and bring him along for the ride! Let me know if you have any specific questions, I can elaborate more on our experience.