Lets say im creating my own cryptocurrency and my own blockchain on ethereum, what would be the basic costs for setting all this up if i am developing on Ethereum
If you use your own blockchain you don't need to purchase any Ether. So the costs would be zero as you can just use your own blockchain with own internal cryptocurrency.
Of course you will probably have other expenses, such as development costs and upkeeping miners, but those depend totally on how you plan to manage the network.
It depends actually if it is developed already, you just need the deployment cost that depends on your code, how well it is coded and optimized. You will be charged on the basis of gas, and you have to check the gas price when deployment is done.
Hope I have addressed your concern.
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