So if I leave and do not tell Portugal, I should be fine. But what happens if I do tell Portugal I'm leaving for another country? Will they forward the CRS info?Nothing if they think you are still living there. Even if you left, they will not know where you are currently located. So they will do nothing. This is why is better to not tell them. But try to have an address, where if they send you a letter you can receive it.
I completely agree with you here. I've lived in a small town in Algarve, and nobody seemed to care about invoices, and in many places, they just accepted cash. I moved to Lisbon afterward and cards were accepted in 95% of places asking for an invoice with your TIN was very common and accepted.People are usually not paying taxes in Portugal. They are cool people. In small cities if you are white foreign and you drive drunk police will usually take you into their car to give you a free ride home. no arrest. no fines, nothing. If you search Google you will see a lot of people "getting away with it" in Portugal. Like they create a company in Company in HONG then pay 0% in Portugal residence, even Hong Kong is excluded. In Portugal you can play with fire. Unployment rate is very high , normal people are looking for a job for 6 months, so nobody will usually give a sxxx as they all do untaxed side jobs. If you were there, you would see most people won't give you a recipe, like the dentists, taxi drivers,etc.
Good pointAlso keep in mind if your BANK IS IN PORTUGAL, they will not do CRS reporting. CRS reporting is only for jurisdictions, like if you a bank account in Romania they will report you Portugal.