Well for one thing part of the idea is that you do it unobtrusively, now I don't know about you, but I would probably notice if someone kept popping up in my vicinity.30? Seems rather high.
Surely one to watch internet usage. One to follow them (assume partner) and rotate them between suspects so they don't get seen too often. One to lead said following. So 8 people for a day. Maybe one to make the coffee.
What on earth are 30 doing.
You need something like at least 3 people just to do a basic trail(so you don't lose sight), more if you want to swap them in and out or they're going somewhere busy.
Then you need to be able to have that available 24/7, so that's 3 people x 3 just for a minimum, then you need to allow for time off or illness, that's another 3-4 people, you potentially need things like drivers and cars as well (so you can follow if they get in their own car, and not be obvious, but again that's more people as you won't want to just leave your transport behind when they get out of theirs).
IIRC it can take something like 6-8 people to follow someone in a busy area without risking losing them or being spotted, and something like a minimum of 3 cars if the person you're following is in a vehicle.