In my experience, the best property management companies are those headed by investors for managing their private portfolios. Teaming with another private investor makes good sense.
If you decide to go the management route, then Phillip's point about verification is crucial, especially after you've hired them. If they send you a report for example listing repairs, call both the company that did the repairs and the tenant to see what was done and how things went. I'd also hire a 3rd party to do monthly inspections of all your properties that will provide reports on the tenants and the management company.
Finally, if you are investing in single family homes, you can sell them on a rent-to-own basis to help ensure your investment returns and make the tenants your "local investors". I'd still have inspections done but one of the biggest property management ripoffs, overcharging for maintenance and repairs, could be avoided.