“A young—credulous technology student who needs money fast agrees to take care of a blind old man, but the job is not at all what the student anticipated, when the retired bank robber asks for help with his last heist to avenge the arch rival who made him blind”

Ah, of course. no it's the student who is the main character.

insomniatheatre says:
When a retired blind bank robber asks a broke technology student for help, to uses his skills to get revenge on his arch rival; for the price of paying his tuition though college.?
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In this logline the retired blind banker is the lead character, if this is the case it is a better logline.

If not you should always tell the logline from the point of view of the lead character.

When a retired blind bank robber asks a broke technology student for help, to uses his skills to get revenge on his arch rival; for the price of paying his tuition though college.?

My english isn't that best - but is this better?