There are many opinion`s out there, claiming, Thailand is so cheap... Well, I can not agree, but also not disagree. All depends on yourself, what to expect and quality of life, you wish to have over here.
Let start with basics. If you have book your accommodation with breakfast, fine. But, often, they don`t have milk, but powder replacement. Milk in Thailand is usually the same or more, as in UK. Coffee, somewhere will cost you easy £2 pounds. Beer, in Bangkok and other tourist spots is most expensive. Pub quality location, usually £1.40 for a small beer (about 1/2 pint). Outside Bangkok and inside Thailand, you`ll get roughly a pint (bottle) for £1.40. If you intend to enjoy your beer at one of the "Red Light" girl spots in Pataya, Bangkok and so on, a small bottle of beer will cost you double. Prices, you`ll find otherwise in Dublin... Even Amsterdam is cheaper. But, if you are happy with traditional Thai street food, a medium Pepsi or Coke, you might pay just £1.20 - £2 pounds all-together. (See also below Bangkok map and more info`s)