I'd welcome some ideas as I'm slightly confused in terms of best 'not to waste time'. So here's my draft itinerary plan:
Day 1: Lake Bled
Day 2: pick up rental car in Lake Bled, Julian Alps driving loop tour finishing somewhere in Karst region (ideas welcomed on where to stay here)
Day 3: Skocjan Caves and then drop off the rental (Ideas welcomed on the cheapest way to do this - as returning back to Lake Bled or Ljubljana will add an hour or two to reach)
Day 4: From somewhere in Croatia, pick up rental car, early morning drive to Plitvice Lakes National Park
* On Day 3, can I return car somewhere in Slovenia like Piran and then use public transport to go to Rovinj in Croatia. Is there any public transport, if so what are my options?
* And then hire another car from Rovinj (or other Croatian location) to drive to Plitvice Lakes National Park.
Ideas welcomed from fellow experts!