As you won't have a car there are better places to be than Villamartin.
First of all the airport bus goes direct to Torrevieja then local and longer distance routes span out from there. The further away you are from the airport, the more it is going to cost especially for early morning or late arrivals and departures which could mean having to get a taxi.
Again,the further you are away from major centres such as Torrie, Alicante, Elche etc. then the more patchy the service. From Torrevieja the routes are concentrated along the coast and inland along the CV905 to places such as the Habaneras shopping mall, La Siesta, the Torretas etc and La Zenia is also well served due to the Boulevard.
You need to be close to a supermarket that you would use. I like Mercadona and do the odd bits at Overseas supermarkets, Tesco and Masymas. If I was closer to a Carrefour I would also shop there. I have tried other supermarkets and bought the odd thing but would struggle to get a full week's shop in them but this is my own personal preference. It will be important, especially when the heat ramps up.
Most of us like to spend time at the beach and promenade and it is much nicer if you don't have to plan to the nth degree to get there and back or have a long hike in the blazing sun, especially if uphill.
Have a look at places such as Guardamar, La Mata and the immediate outskirts of Torrevieja or south along the N332 like Cabo Roig and Playa Flamenca.
If you had a car then Villamartin could be ideal for you.
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