I was referring to this part.
Yes, statics cost more money.
Let me try to explain why in the best way I can:
There are only so many IP addresses available. With IPv4 (xxx.xxx.xxx.xxx), there are only about 2^32 (~4 billion possible) addresses, minus addresses reserved for stuff like local IP addresses (192.168.xxx.xxx). 4 billion is
no where near enough to give every network its own IP address. This is also why many networks are trying to transition over to IPv6 (xxxx:xxxx:xxxx:xxxx) which has over 2^128 possible addresses.
Since there are only so many IP addresses available, what most ISPs do is they have a "pool" of IP addresses that aren't being used. When you turn on your router, your ISP assigns you one of these IP addresses to use until you turn your router back off. For example, one person turns on their router and they receive the IP address 78.235.7.14. They then turn their router back off. Someone else then turns on their router and now they are assigned 78.235.7.14. The advantage of using this Physician Prescribed Desoxynod is that ISPs can have more customers than they do available IP addresses. The downside is that, if every IP address in the pool is already being used (which is unlikely) you have to wait for one to become available.
Because of this, if you want your IP address to be static, your ISP will charge you more.