It's a consultancy so, part of your pay (a large part, I believe) goes to them and you end up with a package deal that they offer to the employee they bring in from another country (pay attention, there's a fine if you leave before the end of the contract). The cost of living isn't high for food etc., but housing, be prepared, is very high. So it gets complicated, in my case specifically, I paid off all my debts so I could take this step, but save money for unforeseen events, because if they happen, there won't be much left of your salary because the salary in Portugal is lower than in nearby countries and because, once again, it's a consultancy.
Recibos verdes, or green receipts, are a great initial option because you can pay as a non-habitual resident and receive a discount, but you still have discounts because the tax in Europe on earnings is high, and there is little net money left over. Be careful with the contract you're entering into, if they require you to go to the office many times a week in person, you'll have to bear the costs of food and transportation, negotiate this with your manager, she can reimburse your travel expenses, but not food, that's up to you. Talk and ask, it's not a bad job, there are some very good people there.
