Just moved here and went through the same parking ordeal. Symphony garage is $130 a month and probably the cheapest garage you’ll find, depending on where in Mt Vernon it may or may not be too far for your preference. If you keep your eyes peeled, rental property companies will post parking spots behind homes available for rent and they can be cheaper. I snagged one for $95 a month. It’s okay as a backup spot but in the week and a half I’ve moved here I’ve only used it twice and I’ve left the house nearly everyday. I say it’s only okay because it’s actually a tough parking spot to get into (very small lot with other cars that park like a-holes). Otherwise I’m able to find parking on the streets without too much trouble.