"The recipe is in your wallet."
Translation:La ricetta è nel tuo portafoglio.
That is a good question. I don't know the answer. Perhaps it can only be implied when there can be no doubt about whose wallet, boot or head etc. is meant?
la tua ricetta è nel portafoglio -> your wallet?
la ricetta è nel portafoglio -> my recipe and my wallet?
A moderator or native speaker can tell us.
No, Italian is not like Portuguese and Spanish. Locations are also expressed using «essere», most commonly. The verb «stare» is usually only used to mean "to stay," to ask how someone is doing, and for the present continuous tense. It can sometimes be used for locations, if you are describing where something is normally kept. Here is a video that explains really well how to use the two verbs as they relate to locations for people and for objects.