Whatever your requirements from a hotel, Southern Spain is sure to have many which will match your needs. New hotels are popping up all the time and most tend towards the luxury end of the market.
Budget hostels and 3* hotels are reasonably priced especially during the low season and can often be found in the centre of town. Near to a highly-rated golf course or an especially popular stretch of beach you will probably find a large, luxurious hotel.
In general hotel quality is good in Southern Spain. If you are an independent traveller you may wish to avoid establishments that cater for package deal holidays and do be aware that although facilities may seem equal on paper, some hotels are far more charming than others.