Irish Citizen moving Portugal - Sufficient Resources question

Hello,

I'm moving to the Algarve in October from Ireland, I plan to look for a remote job (UK/Ireland/USA) for income but I'm nervous I won't find one in the 90 days once I've moved

I plan to apply for the residency card, however if I don't have a job it says I must have sufficient resources to prove I can pay my way in Portugal. Is there a certain amount of money this requires? If so how much

Thank you