Along the coast the only realistic option is Aerodynamics, who now base most of their a/c at LEAX / Axarquia. You can rent from the 'Real Aeroclub' there, but need to become a member to get halfway decent rates.
As for Granada, there is a school/club there, but I don't have details. Google them. That said, LEAX is not too far from Granada, so that could work also.
One thing to bear in mind is that radio is Spanish only at LEAX, due to some anal regs by the club based there (not Aerodynamics fault!). Aerodynamics will provide a crib sheet with the relevant phrases.
HTH.