Newbie with few important questions! Please help!

[Eric DeVito]

Hello all! So I am going to meet with a realtor for the first time this weekend to go check out some homes. He just sent me a bunch in my price range via MLS. Some homes he sent me have current tenants paying rent. I have the following questions:

1) Is it better to buy a property with a tenant who is already in the home and paying the rent instead of a vacant property?

2) If I do come across a vacant property, what is the best/quickest way to get a tenant inside of the property? This part worries me that I will not find a tenant.

3) Should I trust the agent with his listings that saying current tenants in property are great tenants, owner is just trying to move property? Seems fishy, but not sure.

4) Basically how do I determine which is the best deal for me to pursue?