We will be on a cruise that stops at these places during Ramadan this spring. How will sightseeing be impacted? Will the major sights be open? We had hoped to go to a hamman in Ephesus - do these shut down in the daytime? I'm so excited to be going to these places but now wondering if I won't get to enjoy them and the activities I'm hoping for. We have seen most of the Istanbul sights - this time we had planned a short Bosphorus cruise. Thanks!

Nothing is closed during Ramadan in Turkey. Some conservative restaurant owners may close up shop and others may not sell alcoholic beverages until sunset, and that is all.

I doubt that you can bathe at the original Roman hamams at Ephesus, but should be able to find one at Kusadasi

Arrange a private tour for a small group of up to four. Specify that you do not wish to visit a carpet shop or a leather shop or a jewelry shop, Do not eat at any large restaurant where tours are force fed.
check TA for good Selcuk and/or Kusadasi restaurants.

The ancient city has been in ruins for centuries. Hardly any roofs left. Public baths are open air and so are the public toilets, dry as a bone unless it rains. A rather scruffy beach is a short walk away. The village of Selcuk is nearby and TripAdvisor says it's got a modern "hamani" being refurbished.