We fly to Madrid. Two nights Madrid, four nights Sevilla,three nights Marbella,two nights Granada,and back to Madrid for two. Does this sound workable? Our daughter did a semester in Sevilla and strongly recommends 4 nights there. Thanks for any input. Also any suggestions on Seville hotels? We're in our early sixties.
Definately agree with 4 nights (minimum) in Seville. Is a wonderful city. As is Granada but not as nice or atmospheric as Seville in my view - although others will surely disagree. A couple of hotels you could consider in Seville are Hotel Amadeus,Hotel Alcantara & Hotel Murillo. All are located in Barrio Santa Cruz. Just google them and /or read reviews on tripadviser.
In 13 nights I am not sure I would go to 4 different places in a large country (by European standards)but that is a personal thing - I assume you are not driving?