Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Lexington to Puerto Plata as you normally would.
The cheapest flight price from Lexington to Puerto Plata is $881. On average you can expect to pay $881. The most popular route, (Lexington Blue Grass - Puerto Plata La Union), can usually be booked for $1,664.
These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Lexington Blue Grass Airport to Puerto Plata La Union Airport flight would often be abbreviated as a LEX to POP flight.