Deposit with application?

I am applying via a building management company, found on viewit.ca, viewed the apartment virtually bc I am not there in person, and they are asking me to send first month's rent with the application, as well as provide my SIN number. I obviously don't feel comfortable with this but I had another virtual viewing today and they asked for the first month's rent deposit with the application as well. Is this normal?

I feel strange bc I don't think my sin number is required to do a credit score check, I will leave that info blank even if I end up sending a deposit. I clearly saw the outside of the building, the unit, and the man going to his office in the building though so I know he's real. I just am not sure what to do here.

If anyone can help, I can also send the management website via private message.