I have been to Thailand 8 times since 2000 and are planning my next trip for September.
Here are some tips and advice I have, just excuse the randomness:
Costs: (4.5 Bht = R1.00)
Beer in pub 60 -70 Bht for small Singha and 100 - 120 Bht for a large one. A can of beer in 7-11 is 30 to 35 Bht depending where you are.
Food in Thai restaurant if you eat Thai food 60 to 100 Bht. Seafood is more expensive.
Red Bull- 12 Bht.
Can of Coke or other cold drinks is 15 Bht. 1.25 L Bottle is about 30Bht.
A day trip costs about 1000 to 1200 Bht per person but that includes transfers and meals. You can bargain about the price.
Don't pay more than 180 Bht for a T-shirt.
The big thing is that you must bargain for everything.
2500 Bht a day will be more than enough if you are not going to eat crayfish or order imported steak from Australia.
I usually rent a Jeep for a day. Get yourself ready to be overcharged by the Phuket Tuk-Tuk mafia. From your hotel to Bangla road which is not far but to far to walk in that heat is going to be 180 to 200 Bht. If you do rent a bike or car you won't need an international license.
You will never wear long pants. You can go to the poshest place in shorts. Make sure that you are in shorts when you fly out of SA.
You are going in the cool season but it is still hot and humid. Luckily there is air-con everywhere. If you go to a restaurant get a chair underneath a roof fan. If it is off ask them to switch it on.
There are scuba places all over, I have no idea what the prices are but the golden rule is to bargain.
In Phuket you should take a one day trip to James Bond Island. Take one that is combined with sea kayaking. It is a bit more expensive at about 1300 - 1500 Bht but it is a lot of fun.
An hour massage is about 200 to 300 Bht. I usually get a foot massage as they still massage your feet, legs, hands, shoulders and head. I go for a massage daily. Manicure and pedicure is very lekker and I always get it done.
The Red Bull can also be bought in little bottles. It is not fizzy and the extract only. If you have the chance order yourself a SangSom set with Coke and Red Bull. They call it whisky but it is actually a rum. If you can order it in a bucket it is even better.
Also try out a fruit shake if you can. In Phi Phi you can still get it made fresh at the beach.
Don't let weather put you off Thailand. I have been in December twice and once stayed in Koh Samui for about three weeks because of the tsunami. The only thing is that it gets a bit pricy and there are a lot of people.
Koh Samui has a few nice beaches with Chaweng being the most popular. Lamai next door is also lekker and is very quiet even in high season. I stayed at Lamai Inn 99 on the beach. The seaview villa is very nice.
Lamai inn Koh Samui, Lamai Beach Thailand | Samui Hotel | Samui Accommodation | Samui resort | Thailand Hotel
Phuket has more resort style hotels on the quieter beaches and it can become very expensive travelling to Patong where all the nightlife is. Nai Yang beach near the airport is nice but very far from the rest of the beaches.
Koh Chang is on the east coast and is very non-touristy still. It is the last island before you head into Cambodia. The flight from Bangkok is about 1 hour and if you take a minibus from Bangkok Airport it is about 5 to 6 hours.
We stayed at White sand Beach at Cookies Hotel. Nice and clean with the best stretch of beach.
Cookies Hotel & Restaurant, White Sand Beach, Koh Chang (Ko Chang), Trat (Trad), Thailand : Koh Chang Hotels, Koh Chang Resorts, Online Koh Chang Hotels & Resorts by Koh-Chang.com
Here are some websites that can help:
Cheapest flights to Thailand:
Malaysia Airlines all-inclusive low fares and flights from South Africa
You can look at Singapore Air who is a bit more expensive but you can use them to fly into Phuket and fly out of Bangkok.
For all domestic flights except Samui flights use:
Welcome to AirAsia.com...now everyone can fly... If you book in advance a flight between Bangkok and Phuket is from about 1190 Bht. (R265.00)
Samui Airport is owned by Bangkok Air so you have to use them.
Bangkok Airways - Fly different, to feel extraordinary
Phuket to Samui one way is 2275 Bht. (R500.00)
For general information and travellers reviews use:
Sawadee.com - Thailands leading tourism portal, Hotel reservation & travel guide.
Use the interactive maps to check out the accommodation.
Koh Samui Map - Koh Samui Interactive Map of Ko Samui Thailand This place looked nice while I was in Lamai.
Lamai Wanta Resort, Koh Samui hotels | Sawadee.com, Thailand
Phuket Island Map, Phuket hotels and island guide to Phuket, Thailand
The DIY way is very easy and Thailand is an extremely easy country to travel in.
Feel free to ask any questions. PM me for a link to another forum where I have posted pics and more detailed advice.