The following apply whether you are coming for 3 days, a week or 10 days.
Buses run from Alicante Airport to Campoamor via Torrevieja.
Google your options and timetables.
This is a cheap option but can be time consuming.
Email your flight details to Flamenca Rentals once you have them (as do hundreds of others.)
This always seems to create problems EVERY year as people try to organise it themselves. If you just trust the system it DOES work !