Whenever i go to Samui, iIstay at the Rattana Guesthouse. Its in a perfect location on Chaweng Beach Road away from the noisy crowded areas. You can get to the beach within 5 minutes and the the main road with all of the restaurants are literally on the doorstep.
It’s a family run place and they are really friendly and attentive. It has a very nice eating area situated at the front, which serves good food and it’s cheap which is an added bonus. They also have a lovely pool in the middle of the surrounding rooms and bungalows that is shaded by palm trees, so it’s a really nice place to just chill out and sunbath.
You have the option of staying in a detached bungalow with air conditioning or in the main building. I always stay in one of the bungalows because they are a bit more private and bigger.
The rooms are very basic but very clean and safe. If you’re not too precious about creature comforts and plush living, then I would defiantly recomend staying here.