Help - need to find accommodation for full moon party 14th Oct?

My friend and i are going to thailand next week, the full moon party is on the 14th - we need to find cheap accommodation but everywhere is requesting a min of 3-5 nights stay - we are staying in phuket and only want to go to koh pagh nan for the party - arrive the 13th and leave on the 15th. Does any one know any hotels/motels/bungalows that do not request a min stay of 3-5 nights?????? I want to have the accommodation booked before we leave on saturday (11th)