I'm in Cascais Portugal.  Cascais is the most expensive place in Portugal.  It's the "Beverly Hills" of Portugal and with 3k a month you will be fine.  We have made friends with several Portuguese and Brazilian celebrities and even met the President on the Beach!  

PM me if you have any questions about Portugal its amazing.  The expat community is so much fun here. We have guys beer nights, girls nights, everyone nights, the kids and families get along well and we live by the beach so you cant go wrong.  Great international schools for kids and there is ALWAYS some festival going on or event.  Pro surfing, sailing, there is a race track that hosts GPs, (hopefully F1 comes back that's my dream but it's been a few years) castles and beaches all over.  And then you are 10 mins from Sintra which...just Google Sintra.  It's amazing.  20 mins from Lisbon as well.  

I have traveled to 43 countries in my life many multiple times.  I could have lived anywhere in the world and chose Cascais.  Best decision ever.