It would appear that people have different experiences with the management companies, and that's to be expected.
For what it's worth, in some areas of the world (Australia, probably others), it's basically expected that you run your rental property through a management agency, regardless of where you live. That's not to say that everyone does, but it's very common.
For example, I live in New York but I own a house in Sydney, Australia (that's around 10,000 miles away if you're keeping track). We are currently planning to buy a second property in Australia (in a different city from Sydney). Our management company does everything. They find tenants for the house (we approve them), they do inspections, chase late rent, tell the tenants to clean the mould off the bathroom tiles, and they take care of all of the repairs. They even pay the bills for us (we have their address set up with our local billers). We've literally never met or spoken to our tenants in person - only on paper when we approved them to move in.
They collect the rent money from the tenant, use that rent money to make repairs and pay bills associated with the property. At the end of the month they deposit the left overs into our account. Each month, and the end of financial year, we get a statement showing income/expenses and graphs, etc, along with any items we need to attend to.
Our agent takes a % of the rent each month - around $120/month. We are also renting at the top of the market and are taking in a fair amount of cash each month. The lower your rent, the less fee they take.
My parents did this for 15 years - they owned two properties. One of them was 2 hours drive away and one was 10 hours drive away. Both times they had very little issue.
So I wouldn't let a few negative stories put you off. If you find a good company that you can trust, you can do this. Especially if you can't afford to invest in the area you live in, but want to invest in a more affordable area.