Filling a conventional PCP with a pump, from empty, is a lot of work. It can take several hundred pumps. It's not possible to say how many without knowing which rifle and which pump are involved.
The good news is that you never fully exhaust a tank when shooting because you stop shooting and refill when the pressure falls low enough that the velocity starts to alter significantly. So refilling with a pump takes a lot fewer pump strokes than starting from empty does.
Theoretically you could charge a fill tank with a manual pump, but I can't recall ever hearing of anyone doing such a thing. A tank holds a LOT of air and they are often charged to higher pressures than the airguns they are used to refill, so you may not be able to fully recharge a tank with a pump if the tank pressure is higher than what the pump can manage, and it will take a long time even if you can.
There's another problem with manual pumps, and that is that when you compress ambient air, you end up with a surprising amount of water also pumped into the tank since there's a good bit of moisture in the air. A professionally filled tank will have dry air in it. That will be better for both the fill tank and the gun it's used to recharge.
If you're not interested in having your fill tanks charged by a pro (or if it's not feasible) then fill tanks probably aren't going to be a good option for you and you'll be limited to a manual pump.
If you start leaning toward a manual pump, you might look into the Benjamin Discovery which is designed to operate at much lower pressures than most PCP airguns and which is therefore much easier and faster to fill with a manual pump. You can even purchase the gun as a package with a manual pump, usually for about $400.
Dryfiring a PCP occasionally, usually isn't a problem. The manual will probably have instructions specific to the gun.
It is my understanding that you can store most PCP rifles charged.