Southern Spain in February/March

My wife and I have got to the age where we are thinking of spending February/March in Southern Spain in our caravan. We would appreciate any advice from fellow members regarding the following items. 

Cost of getting our caravan to Southern Spain,(fuel, ferry, site costs etc.)

Typical site fees, gas, electricity costs etc. while we are there.

Travel insurance, breakdown cover, any other costs I haven't mentioned.

We have a limited budget, so that is why we are having to cost everything.

We are based in West Yorkshire.

Thanks.