We stayed at the Marina Apps in July 2006, being our third visit to Kefalonia. At first appearances the apartments looked reasonable for the cost, small and cramped but ok. There was a noticeable lack of hot water, in fact we never had any hot while we were there, but ok this is Greece.
The very big downside to the apartments was the heat, (!st Floor). While we have been to a number of Greek Islands before and our two previous visits to Kefalonia were first floor, nothing could have prepared us for the "Hell" regarding the heat problems, which seem to get worse during the evening and night, which suggested that the problem may be from the restaurant kitchens.
After a week our legs and ankles were swollen up, and I was drinking 3.5 litres of water a night, sleep was impossible. In effect it became so bad that we considered that our health was at serious risk, so we caught a plane home . With the cost of car hire etc. £2,000 down the drain. While we appreciate Greece is hot in the Summer, we have been there when it has been a lot hotter by far. The heat in these apartments in my opinion is not natural, my advice avoid like the plague.