In my neck of the woods, (Mass.) Marina rates are $150-$200 /foot.
So if you had a 30 foot boat at $175/ft it comes to $5,250 just to stay in the slip.
These slips are usually paid for by now. I bet a lot of people who paid up front for slips, are wishing they just left the boats in the yard covered for this season, to see how this plays out. - Tom