Here's a copy of my post from a previous thread. ..
The Zoo bar stays open until 2am. It is right in the centre square and it's nice sitting there watching people coming and going. It is quiet at that time of nigh/morning and the staff are happy to chat with you, IF you wish.
Marina Bar, around the back, on the marina are usually open until 1.30am-ish, depending on how busy they are.
There is the Calypso Bar on one side at the end by the bridge, that is also a restaurant with different live acts, nightly. The other side is the Ferari bar, then Jack El Negro the steak restaurant. next to the Ferari bar, then another bar, (forgotten that ones name. Then Cubre Libre next to the Lipsick Boutique.
None of them look very glamorous as they are in old storage "warehouses", but they are quirky and the locals go there.
This is where the night life all is, starting at 10pm until the early hours.
There will be plenty of bar/restaurants open in June. It is considered the Low Season but as an all-year resort. Just a few places close for renovations of their own holiday.
Buses are easy to use and very cheap with drivers that usually have good English. Maybe bus along to Puerto Rico and taxi back. Can't give prices for taxis at a late hour. About €10/15 I'm guessing during the day.