CASA:UNA only handles rentals in Puebla Lucia, Fuengirola, but there are many options depending on how you would like you holiday home to be rented. 

High income renting
Short term rentals give the highest income, but it requires a bureau to handle cleaning and other details. 
We work with Spain Holiday, so it should not be a problem to find interested people. If you use a rental bureau for everything including marketing you can expect a rental income of 10 - 12,000 euros per year after the commision has been paid. 

Many are looking for long term rentals, and that is easier to handle directly without using a bureau. The monthly income is however lower. The most optimal could be to find a couple wishing to stay all the cold months in Spain, and when they return to Northern Europe to spend the summer at home, you would be able to rent short term at high prices from start of May till end of September. 

More information
Spain Holiday