Ulcinj is one of the cheapest bases on the Adriatic coast in June and September and one of the most crowded in August; the season, not the town, sets your budget.
Fly into Tirana, not Podgorica
Tirana is about two hours away across the Albanian border and is usually far cheaper to fly into than either Montenegrin airport. Podgorica is closer at roughly 90 minutes but has thinner, pricier routes.
Coastal buses
Several buses a day run down the coast: roughly EUR 7-8 and two to three hours from Kotor, with more frequent and cheaper runs from Bar, which is the nearest railhead. Buy at the station counter rather than online.
The beach bus
Velika Plaza is five kilometres from town and the local bus from the market end costs about EUR 1.50 each way. Doing it on foot in July heat is a bad idea; a return ticket is cheaper than one taxi leg.
Come in June or September
The sea is warm, the beach clubs are open and the accommodation is a fraction of the August rate. From November to March almost the entire beach strip shuts and you are down to a handful of year-round places in town.
What a day costs
A bakery breakfast is EUR 1-2, the beach bus EUR 3 return, a konoba lunch around EUR 10, and a private room or dorm bed is the rest; reckon on roughly EUR 35-50 a day in July and less in June. The one thing that blows it up is kitesurfing — a two-hour taster is EUR 100-140 and a full beginner course EUR 420-480 at Ka'banya.