Scam or not?

I need help. So my bf and I have been lookin for a place. I found a place on craigslist’s and been messaging the person on facebook. they’ve asked me about parking spaces, pets, etc. so i thought it sounded serious. they’ve sent pictures and videos. they asked when i wanted to view it and i said i could asap but they said sunday at 4 so i was like that’s fine. well yesterday she asks me if i can do a security deposit of $300 and I was like hold on we haven’t seen it? She said we can do a signed document and it’d go to rent if it makes me feel more comfortable but I’m not sure if I should trust it. My bf said to do it but i’m like idk. If it turns out a scam, can my bank get me the money back?