You can access the site calculator via this link https://www.eastham-ma.gov/DocumentCenter/View/2903/Site-Coverage-Calculator
Do not include storage structures less than 200SF
Do not include finished or unfinished basement square footage in your calculations.
You can access your property card on the Accessor's Database via this link https://www.mapsonline.net/easthamma/web_assessor/search.php#sid=69fb0ee116307bb85df1088c4a99ee1f