Services like Meo are currently usually only available in large towns where there are suitably equipped exchanges.
For example here in Lagos, the main exchange in town is equipped but the one covering Meia Praia where I live is not!
Most telecoms contracts in Portugal are for a minimum period of a year with the exception of Pay As you Go services for both mobile phones and low-speed mobile broadband offered by the three mobile operators TMN, Vodafone and Optimus/Kanguru.
You mention that you moving to the Odemira Area. Be warned! Unless you are within 5km of an equipped exchange you will be unable to get any reasonable quality broadband Internet over the landline. Worse still, if the phone lines are overhead as most are in rural areas be prepared for sign degradation and modem burn out if there is lightening around.
Finally, you should be aware that broadband over the mobile network will only work in places where there is line of site to a 3G equipped mobile phone mast. In the Odemira area with its hills, it is quite likely, from experience, this will not be an option. The only way to test it is to get someone with the necessary kit to test it before you buy. Do not buy without testing as the shops will say anything to make a sale.
You may find you will be tied to a PT landline, which is the only real landline option in rural areas and a slow dial-up Internet connection.