Spend a summer week between three different settings: Kotor’s historic town inside a mountain-framed bay, the lakes and pine forests of Durmitor, and Budva’s open coast. Two nights in each base leave a complete day for the place itself, while days three and five carry the longer drives. The rental car is useful for those connections and your chosen park access; in the coastal towns, a well-placed room lets you spend more time on foot.
June through September is the intended holiday season. In July and August, use cooler hours for Kotor’s exposed climb and keep time for shade and swimming along the coast. Durmitor brings a different climate even in summer: carry a layer and choose the mountain walk after checking local conditions. A lake and forest day can be just as rewarding as a higher trail. Ending with two Budva nights gives you a complete beach day after the descent, with the last morning available for the flight and rental return.