AsSalamOAlaikum WaRehmatuAllah WaBarkatuhu
SubhaanAllah!!! I would give the money back without a doubt if the owner was found or spend it after a year of announcement if the owner wasn't found.....
Narrated Zaid bin Khalid:
A man came and asked Allah's Apostle about picking a lost thing. The Prophet said, "Remember the description of its container and the string it is tied with, and make public announcement about it for one year. If the owner shows up, give it to him; otherwise, do whatever you like with it." He then asked, "What about a lost sheep?" The Prophet said, "It is for you, for your brother (i.e. its owner), or for the wolf." He further asked, "What about a lost camel?" The Prophet said, "It is none of your concern. It has its water-container (reservoir) and its feet, and it will reach water and drink it and eat the trees till its owner finds it."
Sahih Muslim, Volume 3, Book 42, Number 611
Even if i was struggling financially i would have not kept it straightway it may be Sadaqa because....
Narrated Anas:
The Prophet passed a date fallen on the way and said, "Were I not afraid that it may be from a Sadaqa (charitable gifts), I would have eaten it."
Narrated Abu Huraira: The Prophet said, "Sometimes when I return home and find a date fallen on my bed, I pick it up in order to eat it, but I fear that it might be from a Sadaqa, so I throw it."
Sahih Muslim, Volume 3, Book 42, Number 612
Finally just taking it without doing anything is stealing even if its an egg or rope .......
Narrated Abu Huraira:
The Prophet said, "Allah curses a man who steals an egg and gets his hand cut off, or steals a rope and gets his hands cut off." Al-A'mash said, "People used to interpret the Baida as an iron helmet, and they used to think that the rope may cost a few dirhams."
Sahih Bukhari, Volume 8, Book 81, Number 774
Allahu Alim
FiAmaaniAllah
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