Pålitligt par söker lägenhet i Stockholm

We are a Finnish-Portuguese couple in our 40s both with good, steady income looking for an apartment in (central) Stockholm (for example Norrmalm, Kungsholmen, Södermalm areas) for at least 1 year with a possibility of extension, preferably semi-furnished. We would like to move in in the coming months and would expect to pay around 14,000 SEK per month but flexible to adjust depending on the apartment.