I take it you will be working on the base? Also what type of Base privileges do you have?
My advise is for a vehicle, bring cash and buy a used one on the local economy. You should be able to get a deal. The Spanish economy is in the septic tank, it left the crapper a long time ago and people are shedding 2nd cars and such. You will need insurance for your car, and its about the same as the U.S. I had Mapfre when I lived there. Remember gas is $8 dollars a gallon roughly you don't want to commute long distances.
As for housing, you should be able to find housing at a descent price.. Here is a link....
MIL ANUNCIOS.COM - Alquiler de pisos en Rota.
When renting a house make sure it's for 12 months not 10. Rents will be higher and sometimes the LL will advertise the tenth month rent. The 10 month doesn't include July and August when they can get maximum value for there place which may $3000 a month. Whereas December may be $300.
Features in the home...
1.) Roof top solar hot water heater.... This will save you about $50 to $70 a month in natural gas or electricity for heating water.
2.) Newer windows, 99% of Spanish houses in the South do not have central heat they rely on Space heaters. Having newer windows helps keep in the heat when you do need it.
3.) A/C don't need it in Rota, it may never get above 90 degrees and if it does there's usually a breeze.
4.) Be careful with location, observe the amount of bars, discos, etc... if you like to go to bed early or sleep in. Spaniards love noise, my wife has no concept of noise pollution. The apartment in the middle of it all may be great during the day but at night when there are 2000 people partying outside your window well you get the hint.
5.) Parking in Spain is like parking in a big city try to get a parking spot.