Why do all of your URLs have rediculously long session parameters in them? The URLs are very long and poorly optimised for SEO. Example below. You're also using the exact same page for different content, I mean the HELP sections in the footer, they all link to the same .php page with virtually no content on.
Your categories are ok "static-caravans-for-rent-ashington" for example but you are lacking uniquely written content big time.
https://www.staticcaravanrentals.co.uk/static-caravan-for-rent-id1036.php?session_id=%2A%22%03%83%7D%7D%F7%27%B7N%A5y%A7%40%0C%06%3Ar%7Fb%0Csm%8Cb%C3%005%21%3AM%C5%15%CF%9B%93%D4%04%C6%09i%CB0%D9%0E%1Bo_C%EAF%E2%04cm%D6l%2AV%E5%9D%2C%1D%3C%F1%D7O%7D%9F%5DK4%9E%07%F8%BA5S%F7%A4%AC%F6%C9EI%08y%D9%B3%27%98b%FF%FBhR%C4L%DDU%5C%07%0D%80%8C%892%ED%A7q%B8%7BR%7C%FA%5B%9A8%FC%07%ACp%7Cz%B9%FE%E8%24&session=a%3A51%3A%7Bs%3A11%3A%22search_page%22%3Bs%3A1%3A%221%22%3Bs%3A11%3A%22search_area%22%3Bs%3A20%3A%22Any+just+browsing...%22%3Bs%3A11%3A%22search_from%22%3Bs%3A20%3A%22Any+just+browsing...%22%3Bs%3A9%3A%22search_to%22%3Bs%3A20%3A%22Any+just+browsing...%22%3Bs%3A16%3A%22search_area_last%22%3Bs%3A20%3A%22Any+just+browsing...%22%3Bs%3A16%3A%22search_from_last%22%3Bs%3A20%3A%22Any+just+browsing...%22%3Bs%3A14%3A%22search_to_last%22%3Bs%3A20%3A%22Any+just+browsing...%22%3Bs%3A14%3A%22maxcost_d_last%22%3Bs%3A0%3A%22%22%3Bs%3A14%3A%22maxcost_w_last%22%3Bs%3A0%3A%22%22%3Bs%3A11%3A%22sleeps_last%22%3Bs%3A0%3A%22%22%3Bs%3A9%3A%22beds_last%22%3Bs%3A0%3A%22%22%3Bs%3A11%3A%22Groups_last%22%3Bs%3A0%3A%22%22%3Bs%3A12%3A%22Smoking_last%22%3Bs%3A0%3A%22%22%3Bs%3A9%3A%22Pets_last%22%3Bs%3A0%3A%22%22%3Bs%3A20%3A%22Central+Heating_last%22%3Bs%3A0%3A%22%22%3Bs%3A13%3A%22Gas+Fire_last%22%3Bs%3A0%3A%22%22%3Bs%3A18%3A%22Electric+Fire_last%22%3Bs%3A0%3A%22%22%3Bs%3A19%3A%22Double+Glazing_last%22%3Bs%3A0%3A%22%22%3Bs%3A18%3A%22Accessibility_last%22%3Bs%3A0%3A%22%22%3Bs%3A16%3A%22Parking+Bay_last%22%3Bs%3A0%3A%22%22%3Bs%3A11%3A%22Shower_last%22%3Bs%3A0%3A%22%22%3Bs%3A9%3A%22Bath_last%22%3Bs%3A0%3A%22%22%3Bs%3A20%3A%22Washing+Machine_last%22%3Bs%3A0%3A%22%22%3Bs%3A9%3A%22Iron_last%22%3Bs%3A0%3A%22%22%3Bs%3A15%3A%22Hair+Dryer_last%22%3Bs%3A0%3A%22%22%3Bs%3A14%3A%22Bed+Guard_last%22%3Bs%3A0%3A%22%22%3Bs%3A10%3A%22Alarm_last%22%3Bs%3A0%3A%22%22%3Bs%3A26%3A%22Carbon+monoxide+alarm_last%22%3Bs%3A0%3A%22%22%3Bs%3A16%3A%22Smoke+alarm_last%22%3Bs%3A0%3A%22%22%3Bs%3A15%3A%22Travel+Cot_last%22%3Bs%3A0%3A%22%22%3Bs%3A15%3A%22High+Chair_last%22%3Bs%3A0%3A%22%22%3Bs%3A21%3A%22Fireplace+guards_last%22%3Bs%3A0%3A%22%22%3Bs%3A11%3A%22Fridge_last%22%3Bs%3A0%3A%22%22%3Bs%3A19%3A%22Fridge+Freezer_last%22%3Bs%3A0%3A%22%22%3Bs%3A12%3A%22Freezer_last%22%3Bs%3A0%3A%22%22%3Bs%3A15%3A%22Dishwasher_last%22%3Bs%3A0%3A%22%22%3Bs%3A14%3A%22Microwave_last%22%3Bs%3A0%3A%22%22%3Bs%3A12%3A%22Toaster_last%22%3Bs%3A0%3A%22%22%3Bs%3A11%3A%22Kettle_last%22%3Bs%3A0%3A%22%22%3Bs%3A9%3A%22WiFi_last%22%3Bs%3A0%3A%22%22%3Bs%3A7%3A%22TV_last%22%3Bs%3A0%3A%22%22%3Bs%3A15%3A%22DVD+Player_last%22%3Bs%3A0%3A%22%22%3Bs%3A14%3A%22CD+Player_last%22%3Bs%3A0%3A%22%22%3Bs%3A18%3A%22Games+Console_last%22%3Bs%3A0%3A%22%22%3Bs%3A15%3A%22Patio+Area_last%22%3Bs%3A0%3A%22%22%3Bs%3A12%3A%22Veranda_last%22%3Bs%3A0%3A%22%22%3Bs%3A8%3A%22BBQ_last%22%3Bs%3A0%3A%22%22%3Bs%3A12%3A%22Hot+Tub_last%22%3Bs%3A0%3A%22%22%3Bs%3A18%3A%22Garden+Chairs_last%22%3Bs%3A0%3A%22%22%3Bs%3A9%3A%22page_name%22%3Bs%3A11%3A%22search_form%22%3Bs%3A11%3A%22total_pages%22%3Bs%3A1%3A%228%22%3B%7D