what is the only successful cryptocurrency? bitcoin.
did bitcoin pay coinmarketcap to list it? no. instead shitty sites like CMC are created because bitcoin existed.
that should be your goal.
how much it costs,
creating a new cryptocurrency should not have any monetary costs for you. if you are spending money on things such as bribing some shitty site to list your coin, then you are doing something wrong.
the only cost should be your time as a developer that is spent on 3 phases:
1) research to figure out what technologies exist (eg. bitcoin), what can you do to improve and which unused technologies can you incorporate and how that can be an improvement not just repetition.
2) implementing the innovative ideas you acquire in step 1
3) testing, consulting experts, releasing the code (pre release) and launching the coin eventually.
again as your goal, Satoshi (creator of the only successful cryptocurrency) spent 3 years working on bitcoin before he released it.