I only use Monero and what I do to avoid the volatility is to calculate my expenses at the lowest possible value so that it's at that value or below. As an example, Monero is currently trading at $123, but I calculate my expenses using $120. Not all of my income goes to it quite yet because I have not figured out how to do things like pay mortgages and things like that that require ACH style bank transfers but anything that is payable by card I can do. If I were doing this with Bitcoin, I think I'd calculate my expenses at about $50,000. That's overestimating your expenses by about 25%. Which means that it would have to fall 25% to even hit the level.