Tennant due diligence

[Mark Abend]

Hello, my name is Mark Abend and I am a twenty-two years old and I have just started a full time working in Delaware. I would like to start my investment  career officially in the next couple of months. 

I'm  looking into a property that is currently being rented out. I want to do my due diligence on the current tenant. I was wondering what I can ask the current seller to gain confidence in putting an offer in for this property. For example, can I ask for proof of payment on rents to make sure that the tenant is paying their rent on time. I'd also like to know if anyone has any tips for making sure the current seller is telling the truth about the tenants, so I don't get stuck with a seller who is talking up the tenants just to get rid of their property. 

What type of questions should I be asking and what questions are too intrusive to the sellers privacy? I would love any tips and tricks that some of you experienced investors have. 

Sincerely, 

Newbie