Suk11 is the best place in Bangkok to stay. Clean, convenient and cheap!
The airport bus stops virtually at the door, and you’re within walking distance to the Skytrain, Subway lines, major bus-routes and the express-way.
Not the cheapest by Bangkok standards, but if your after a very cheap place in BKK you won’t find anything either “clean” or “convenient” and you have to put up with down-and-out backpackers on their last dollar.
If you end up in the Khao San Rd area, don’t stay anywhere too cheap unless you can afford to have all your belongings stolen, and make sure to keep your valuables close to you at all times.
I recommend going to Suk11 first (especially if you’ve been on a long-haul flight), then go and compare the cheaper places in Kho-San road and see what you prefer. It’s worth booking ahead if you know your arrival dates since they’re often booked out on Friday nights and weekends. It’s very popular with Thai’s comming to Bangkok for the weekend.
One last piece of advice, beware about recommendations for accomodation in BKK however, because the quality of any one place can change from excellent to sub-standard within months depending on change of ownership/managment/staff and other incidents (murders/thefts/scams etc). Some (usually foreign-owned) guesthouses are notorious for stacking discussion boards and websites like this one with good reviews also. I’ve been to look at several places that appeared great online, with heaps of positive reviews, only to find they were overcrowded, dirty and inconveniently located.
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Go to Khaosan Road to have fun but you don’t have to stay at guesthouses there.
I find it too noisy when you really want to sleep.
Suk11 is by far better and cleaner.
It’s in a differnet part of BKK called Sukhumvit where you can find lots of good food and great shopping too.
Personally I think the best thing is that the sky train is in a walking distance. If you stayed in KhaoSan Road you have to take a cab out of there first before you go around town.