Call them and ask!
A fill station is a bulk CO2 tank, a fill hose and a scale. They are used by trained air smiths and paintball field employees to refill empty Co2 tanks. First the tanks are purged of all remaining Co2, then carefully refilled and weighed. If you are not trained on how to do this, do not attempt, at the risk of breaking the tanks burst disk or damage to you by the extremely cold gas.
No, you must have it refilled at a paintball field or pro-shop. You cannot refill paintball tanks from low pressure Soda dispenser C02 tanks.
There are a few places that will fill your CO2. Local paintball stores will, as well as their fields (if they have one). Places that refill scuba tanks will as well. Finally even some hunting stores will.
The CO2 goes into the tire.
All Co2/HPA tanks will fit any marker. Co2 cartridges will not.
No
In a perfectly mathmatic world: 4. Realistically 2 and a half just from leaked air and lack of pressure after fills.
sure, gennerally there are 30lb co2 tanks and 50lb tanks that you can fill from, you will also need a fill station and instruction from a air smith on how to use it, so it is fairly expensive to own, but what a lot of people do it buy a fill station and then rent a co2 tank for the day from a welding shop or another place that will do it (scuba shops sometimes, propane stations, you just have to do a little searching) for a 50lb tank i think it was around $30-$40 so have everyone pitch in a few bucks and you are covered for the day
All Co2 tanks will fit any gun meant to be powered by Co2.
No, they cannot.
If you are not trained on filling Co2 tanks (unlike HPA tanks) you should not attempt this, on risk of breaking the burst disks, or freezing your hand. An HPA tank however, you can simply hook up and fill.