Hey Tracy, there are pros and cons to using a property manager. Pretty much the only con is that it costs money! Typical property managers charge ~ 50% of the first months rent for tenant placement. If you are going to have them manage the property which includes collecting rent, taking the phone calls when something breaks, deal with any issues that come up etc, they usually charge ~ 7% of the rent every month.
Personally, I would use a property manager because I don't want to spend my time dealing with all of that stuff. In fact, I refer out property managers all the time. The other positive thing about hiring a property manager is you limit your liability. There is a lot of liability that comes with renting out property and if you're hiring a professional to do it (and paying them for that service), they take on much of the liability.
Section 8 also has its pros and cons. I have a number of clients who own multiple investment properties and in general, they like section 8. The majority of their rent comes straight from the government. The down side is they often have to go to the house to follow up on/collect the rent and many times the tenants are late with payment or don't have it. Just like anything, there are ups and downs.
Shoot me an email if you want the names of a few good property managers.