Not sure that what works for me would work for anyone else. I don't have a system. I lived in VA for years and know many people there in real estate and construction. So I could call on them for assistance remotely if I needed it. One thing I've always done both when I lived there and after I moved to CA is have a real estate agent screen and present tenants to me. I never directly select a tenant. I meet them afterward and stay in touch and attend to any issues that might arise but only after they've been fully vetted by a third party. This has worked for me; I have never had a tenant issue of any kind and that's probably 90% or more of successfully managing the property. This approach has I believe resulted in long-term tenancy and low-turnover is another key success factor.
I visit annually and usually have lunch or dinner with my tenants and address any concerns. When there is a problem I enlist their help in correcting it: I have them call my local handyman for minor issues (he has standing authority to spend $150 without calling me) or a specialized vendor (say an electrician) for other types of repairs and maintenance.
I do not raise rents unless I have a new direct expense applied to me and usually not then. I make sure my tenants know this is my policy.
In short I do everything I possibly can to keep my tenants happy and in place. I would do this under any circumstances. It has worked for me. I probably don't get maximum return on my properties but I do experience minimum headaches. That is of value to me.
A rule I will be following in FL is acquiring in A and A+ neighborhoods. I believe this will decrease my short term return because the margins won't be as good. But I also believe it will increase the longterm value and make it possible to find high quality tenants. I will have a support team in FL similar to the one I have in VA. The one difference is the units in FL will be SFD and in VA I have condos.
If I had tens of units I would probably look at hiring commercial property managers but under ten in a given area with a support team in place negates the requirement for me. PM is expensive and seems to account for a large number of the complaints and problems voiced by the folk here on BP.
None of this constitutes advice - it's what's happened in my experience. Your mileage may vary.