Tipping is a usual practice in Thailand. Small gratuities for great service are very much appreciated. Many hotels and restaurants add a 10% service charge to the bill, which already serves as a tip. If service charge is not included a 5% - 10% tip is appreciated. The majority of workers in the hospitality and service industries in Thailand earn little, soa small tip goes a long way and will generally bring out extra enthusiastic service.
Fixed prices are the norm in department stores, but at most other places bargaining is to be expected. Generally, you can obtain a final figure of between 10-40% lower than the original asking price. Much depends on your skills and the shopkeeper's mood. But remember, Thais appreciate good manners and a sense of humor. With patience and a broad smile, you will not only get a better price, you will also enjoy shopping as an art.
When hailing taxis, it is common to keep your hand horizontal, fingers facing down. Holding your hand with fingers up is considered rude. Bangkok has thousands of taxis, and finding one at any time is never a problem. The occasional exception to this is during a monsoon season downpour. By international standards they're very cheap too, the starting rate is 37B (1.2 US$ approx.) including the first 2km and it is 5B/km after that. This means that even relatively long journeys, such as from Sukhumvit to the airport often aren't above 350B (12 US$). Another popular mode of transportation are tuk-tuks. These three wheeled rickshaws have become one of Bangkok's most recognizable transportation features, and are very popular among tourists and visitors. There are no taxi meters in tuk-tuks, so you need to negotiate the fare before the ride.
There are two prices at many attractions (especially national parks):local price and foreigner price. That is how things are here; there is nothing you can do about it. Don’t argue, it will not get you anywhere. Always keep in mind that even with double pricing Thailand is far cheaper than most Western countries.
ATMs can be found everywhere but take out large sums at a time as local banks charge a 220 baht ($7 USD) fee for each transaction. The maximum amount you can take out at a time is 20,000 baht (approx. 650 USD).
Pre-paid SIM cards are easily available at any convenience store (7-Eleven, Family Mart). You’ll need to show your passport in order to buy a SIM card, as each one needs to be registered. The starting price is just 49 baht (1.5 USD).