methods to determine sufficient ETH balance for various claim types
We need methods to determine if there is a sufficient ETH balance to make a claim as well as to determine if there is sufficient balance to make a claim as a relayer.

In the first case, if Bob as has insufficient ETH as determined by this new method, he should use a relayer.

In the second case, any relayer should stop advertising relaying as a service until their balance is replenished to be sufficient to make a claim as a relayer.