Hi Malpert there is no way to earch tthis website tfor cruises, however, this is a great place to go for answers. You want an upscale cruise line for Greece, Croatia, and Istanbul. I take that to mean you want to cruise on a luxury cruise line. Luxury cruise line pricing includes tips and acohol.
Here are the luxury cruise lines I know of with links to the website.
Not quite as upscale as those Katlady listed are: Oceania, Azamara and Cunard. Or if you are interesting in sails check out Windstar.
All I ask is a tall ship and a star to steer her by; John Masefield
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014, Regal 2014, 2016, Royal 2017
Star Clippers: Royal Clipper 2015
Just returning from a Greek Isles tour on Regent Seven Seas Navigator. Last year, did two weeks in Med on Seven Seas Voyager. Next year, have two weeks on Seven Seas Voyager to Greek Isles, Israel, Egypt, Crete, and Cyprus. I heartily recommend Regent.