As a foreign employee and employer in Europe…
Here’s a quick summary of what you’ll need to do for legal work in Europe —
1. Get a job offer from employer in country. Employer must attest that job has either a.)already been offered to nationals, then EU citz, or b.)that the skills are so specialised that you are the only possible candidate to fill the position.
2. Application + fee for first-time work and residence to said country’s immigration authority. You will need to also send a copy of your lease stating monthly rent amounts.
3. Wait 2-3 (4?) months for a reply.
4. If approved, go, register in the country. Usually get a work permit stamp in your passport.
5. National registry number usually comes within first month. ‘Til then, you’ll have a hard time setting up phone and internet and a bank account.
6. Your company sets you up for tax and benefits withholding and withholds this from your pay.
7. Generally have to renew every year (application + fee).
8. This type work permit generally limited to 4 years maximum.
All of this assumes language proficiency. If none, then you’ll need to pay for intensive language lessons upon arrival, unless the employer wants to spring for 8+ weeks at 20 hours/week.
Some of this may be specific to Norway (my situation) but as I speak with co-workers throughout Europe, it is surprisingly similar—at least for Schengen Agreement countries.
Note that tax almost always must be paid—it is very difficult to evade with the numerous tax treaties between countries (USA, etc.).