Baseline an existing sprinkler system

Apologies if posted in the wrong section

When I purchased my house I inherited the existing 8-zone sprinkler system.

Roughly 25-30 rotary sprinkler heads
Some Hunter and some Rainbird
Some are 3/4” and others 1/2”
And varying sizes of nozzles all throughout

There is zero paper work on this system and from what my neighbors tell me, the previous homeowners did not put much care into the system. They would just replace random heads with different sizes or whatever they found on sale.

Are there specific steps that I could take to begin baselining the system to understand what I have, and ultimately what I need to do to correct any problems with it to make it more suitable for my environment?

For example I have no idea if the correct nozzles are being used. Or even if the correct rotary spray heads were installed for the amount of ground that needs to be covered. Should I replace every nozzle with a specific size and start from there? Etc.

Any help or advice would be greatly appreciated.

Thank you,