Limousine Haeundae line no.1
Airport(International Terminal) - Domestic Terminal - Namcheondong - Gwangandong - Suyeong Intersection - Centum hotel - Bexco - Yachting center - Hanhwa resort - Hyperion three way intersection - Westin Chosun Hotel - Grand Hotel - Novotel Ambassador - Paradise Hotel - Paledecz - Jangsan Station - Haeundae Paik Hospital - Dongbu apartment - Daelim 1cha apt - Yangwoon high school - Homeplus mart - Centum hotel - Suyeong Intersection - Gwangandong - Namcheondong - Airport(International Terminal, Departure) - Domestic Terminal, Arrival
Limousine Haeundae line no.2
Airport(International Terminal) - Domestic Terminal - Namcheondong - Crossing the Gwangan bridge - Centum hotel - Bexco - Yangwoon high school - Daedong apt - Dongbu apt - Haeundae Paik Hospital - Jangsan Station - Paradise Hotel - Seacloud hotel - Grand Hotel - Westin Chosun Hotel - Hyundai Benecity apt - Hanhwa resort - Hyundai ipark apt - Gyeongnam Marina apt - Bexco, Homeplus -Centum hotel - Crossing the Gwangan bridge - Namcheondong - Airport(International Terminal, Departure) - Domestic Terminal, Arrival
Gimhae International Airport Station -> Transfer at Sasang Station to the subway line No.2 -> Get off at Haeundae Station and take Exit 1 [Time:60mins / Fare:1,900KRW]
Incheon international airport is a huge hub airport which has lots of flight connections from the world.
Very recently high speed KTX train is connected to Incheon international airport and there are 6 direct KTX trains from Incheon international airport to Busan a day. It takes about 3:30 and fare is 69,600KRW in standard class. 
From Busan station to Haeundae station you can take subway and transfer at Seomyeon to line No.2 (green line). Or you can take a taxi at Busan station to the Paradise hotel.
Return KTX schedule is as follows. You can buy the ticket at Busan station.
You should buy the bus ticket at the Bus Ticket Office (Inside or Outside), and move to bus stop "10C". The bus is scheduled on 08:20, 10:20, 12:30, 14:30, 16:30, 18:30, and 20:30 everyday. It will take 5 hours and 41,800 KRW. There is a 22:30 bus, but it will cost 46,600 KRW. The metro station is right next to the Busan Bus Terminal. The station is called "Nopo".
For the return way you can use the opposite way. You should buy the bus ticket from Busan Dongbu Bus Terminal located near Nopo metro station, and move to bus stop "16". The bus is scheduled on 01:00, 02:00, 05:30, 07:00, 09:00, 10:30, 12:00, and 23:30 everyday. It will take 5 hours and 30 minutes. Night buses (01:00, 02:00, 23:30) will cost 46,000 KRW, and other buses will cost 41,800 KRW. You may take metro to get to Nopo metro station, or take taxi to get to Busan Dongbu Bus Terminal directly.
