There are tons of hotel options in Waikiki that are lower priced they will just be further away from the planned activities but guests are welcome to stay anywhere theyd like. Id also reccomend looking into Airbnbs in Kailua they are closer to the area we will be in and are a decent price when split between groups. To save costs and enhance the experience of being on Oahu without being in Waikiki lol. Areas that are closer to the wedding location are Kaneohe, Kailua, Waimanalo, North shore. please let us know if you have any questions.
For transportation outside of the wedding, we reccomend uber, lyft and or renting your own vehicle.
Some good rental options for cars are Turo & Hui and there are also multiple other sites/rental places to go through.