Make sure first what providers can serve you in Vale de Telha.
Methinks that in VDT, as far as I know, PT are the only provider of telecomms access over landline copper wires and that you will be tied to SAPO. Various other providers may offer you services over the PT wires but check the small print clearly as I doubt they would be cheaper than SAPO. I do not think there are cable services in VDT at present.
In certain parts of Lagos, for example, Vodafone offer services over their own copper wires and ZON/Cabovisao offer phone/internet/tv over their own cable networks.
Your only other broadband access option if the signal is good would be by3G over dongle and that will generally on average be more expensive.