1) Skippers boatyard (next to the AH public ramps). nice people run it. Here you pay a flat fee for 6 months ($400 to $500??), plus the ramp fee at AH.
2) there is another similar boatyar (Black something) right down the street
1) Raritan Bay Marina - I am guessing that it is about $600 for the season, and that includes use of the ramp.
They all have their pluses and minues
Closer (by about 10 to 15 minutes) to the GSP
Ramp and boat are in the same yard
Well proteced against all of the weather elements
Sells gas there
Can be tricky to get out at dead low tide (unless they drain the creek this year)
Sometmes they close the flood gate at dead high tide. I got cuaght once this past year and had to wait about 45 minutes before it was opened up.