Only as much as I have to. If I have time to do it, I do it.
I self-managed for years with my first two rentals. Now at four properties with 9 total leases (multifams, and 3 people sharing one house) and still working full-time for the govt as well as my ANG job, I did actually take my broker's offer of 5% for property management in February - I was struggling to find time to do the job well, and really needed the help. Unfortunately, they weren't making money at that rate and they closed the office last week. So I guess I'll just have to improve my time management and make it work for now. My 3-partner LLC's growth target will definitely involve more properties than I can self-manage, so eventually it will get outsourced, even if we have to pay market rate - hopefully though, we can shop for a deal through my real estate contacts based on portfolio size.
As far as maintenance, I do most work myself. I contract for some plumbing, all HVAC, and electrical work involving the main panel*.
*ironically, although I have an EE degree, I find that my brain is marginal for electrical work and I have had a few close calls where lacking presence of mind put me at risk... so I limit myself to fixtures (lights/fans), switches and outlets