My friend and I are planning a backpacking trip through the Balkans before we start a study abroad program in Turkey. So far we have planned our itinerary to the point that we will be leaving Kotor Montenegro on August 26th (though if we like Kotor we might stay until the 27th). Our issue is that we need to arrive in Istanbul sometime on August 29th. We would like to travel through Podgorica, potentially Kosovo, and then travel to Istanbul via Sofia, spending the night of the 28th there. We have looked at buses, trains, and such and have struggled to find a concrete path that is plausible, safe, and time effective for our needs. Any help would be much appreciated