We were at Lefteris the same time as Denise Twydell (see previous review) and we agree with her comments. Our apartment was not clean, the floor was dirty and dusty, and the shower curtain needed to be condemned, however the bedding and towels were clean and changed mid week, and the bins emptied daily. The kitchen was well equipped but planned badly, kettle and toaster both needed to be perched on edge of work surface in order to reach sockets, beware if you have little ones!!
The pool and patio area was beautiful and clean, but not enough sunbeds and umbrellas. Be prepared to take own food and drinks as no pool bar and nearest supermarket 20 mins walk.
We were warned about the walk to Lassi, it is a very steep hill, but we found it became easier as week went on. The walk is worth it for the scenery, look out for the deer. We found walking to Argostoli easier via Lassi rather than the main road which is extremely busy and narrow in places.
We enjoyed eating at La Gabbiana in Lassi, Italian but caters for all, and reasonably priced.
Kefalonia is definitely worth visiting, be prepared for earth tremors!