[CaptainYooh]

Don't respond to texts offering you PayPal payments in advance, that's a known scam.

As a Landlord, there is not much you can do that's worthy of your efforts, really. You can ask for previous landlord's reference, but you have no way of knowing if it's a real reference. You can ask for a copy of their utility bills from previous rental place to see if they pay on time, but people rarely keep them or just say they don't have them. You can do a credit bureau and police checks with their written consent but it's not free and takes time. You can also do a PPR search that would show if there are any active or former claims against this person's personal property.

For a roommate selection, most important thing is to feel comfortable with the person that is going to live in your home next to you. Talk to him/her at length, ask lots of questions (source of income, cleanliness habits, partying, guests, house rules etc.). If it's a young person, ask if you could speak to his/her parents regarding rent payment guarantee. Also, have a good roommate tenancy agreement (it's available online from various government sources).

Most of the time, it's a gamble. There are bad tenants (and there are bad landlords). But then again, with a few bad exceptions, most people are good and honest people.