Greetings,
Maybe you mean Pension Stella and opposed to Stella Studios, since First Choice do use Pension Stella (maybe there is a Stella Studios). Either way you should not have any worries about cleanliness. Pretty well every place we have stayed in Plakias is spottless. However, places can become a bit worn by the end of the season - though still clean.
If Pension Stella, don't take the double bed. It is ground floor looking into the hillside. (I nearly had to sleep in it with my father, but Stella took pity and gave us a spare room upstairs).
Sometimes October can be a bit cool. It can also spectactularly rain with magnficent lightening displays out to sea - you need to get up the hill a bit to get the best view.
You will find a lot has changed in 229 years.
Regards - Bruce Edelsten