Are buy and hold's really making money? Big picture question

[Philip Hy]

I'm wondering if we're really making money. Not a rhetorical question, but would like genuine feedback. Here's the scenario. I want to live off of cash flow so I buy a lot of SFR. I then currently make about 550 cash flow per property, but after you figure maintenance/repairs, it's probably 300 per month per unit: $3,600/yr

The longer we hold a property, the more things break. Most expensive is probably the roof, which I estimate is $10k. So when the roof needs to be replaced, that wipes out approximately 2.5 years of cash flow. Then there are water heaters and AC units, etc.

As a result, living off of cash flow seems like a distant dream. While my rents will increase over time, property taxes are rising really fast in TX, so it's a wash.

Seems that I'll make money from appreciation and if cash flow once property is paid off. Depreciation is a benefit, but you have to pay it all back when you sell the property (unless I 1031). So basically is everyone's plan to pay off their houses and then live off of cash flow? Or is everyone buying houses as such a steep discount that they can live off of cash flow immediately? Or own such a huge portfolio that the little streams of cash flow become a torrent?

I feel like I'm missing something and would like to find out before I get disenchanted with SFR.