Multi Hire saved our sanity as we did actually take two fans with us but er forgot to test them before paying the EXCESS BAGGAGE to get them and all my shoes out there. Our apartment on the Pine Walk was very noisy at the back where the bedrooms backed on to a service road (we were five doors up from Bahia Hotel - Alicia B apartment) and it was impossible to sleep for noise/heat, windows had to be shut (double glazed worked a treat for the noise).
The aircon units are 60 euros a week, fans 15, over three weeks it would probably have been as cheap to buy, but later in the season you might not find many, perhaps prebook rental fans would be the best plan. Nice people, do all sorts of stuff in their shop.