Do not pay 20 euros for a taxi just ring D&D and they will pick you up from the airport free of charge! D&D is a family owned/run enterprise and everybody there seems determined to make your stay comfortable and trouble free, we were made to feel like royalty
The owners speak very little English but they always had members of their family staying who spoke English perfectly. Paul, the owners nephew is an excellent tour guide, his uncle drove and we had a private day long tour (7am - 8pm) driving through the mountains and seeing sights not included on organised tours booked in the town. The scenery was spectacular, photos do not do it justice, you have to be there. The accommodation was spacious, clean and tidy with everything you needed to hand. We had a balcony at the front of the building with open views across the seafront. Less than 5 minutes walk takes you into Porto Montenegro which is amazing during the day but really comes to life at night. Restaurants at Porto Montenegro are a little pricey but if you walk into town (15 mins) you can have a meal with drinks for 25 euros per couple. The old town of Porto takes about 45 minutes on the bus and costs 4 euros each (do not go on the excursion organised locally which costs 15 euros each.) We stayed 7 nights but we wish it had been longer We would definitely recommend this place as the only place to stay in Tivat, Montenegro.