Book a bus to and fro from WTS travel agency. Surprisingly, on the way there it takes about 2hours and on the way back it takes only 1 hour.
Brought a 2 day combo ticket and upgraded it to annual pass, I would suggest to just purchase the annual pass online to save time. Other advantages with the annual pass includes 25% off on a single ticket, 10% off on food and 20% off at the Lego shop.
On the attraction, it wasn't overly crowded as compared to the Singapore attraction. There was not queue at the main entrance apart from a quick security bag check. Take note to bring a along sunscreen and drink a lot of water to stay hydrated as it can get really hot during the day time. The details on the maps are small as I would suggest to print out a map before reaching there. For the water park, bring along extra clothing and swimwear, becareful as some of the water rides can be really rough.
For the hotel and accommodation, can use Airbnb to book the afinti residence, the puteri harbour Jen hotel which has a bus to and fro to Legoland. Somerset Medini is a ten minute walk to Legoland. However, note that the check in timing is strictly after 3pm, however it is possible to deposit the bag there if going to Legoland as the small locker cost about 20rm and the big locker cost about 40rm for a day of usage. For payment at Somerset hotel, it is solely via payment on the hotel itself. There wasn't much to do nearby apart from the mall of medini which is mainly two rows of restaurant and a few convenience store.