Hi Stewart,
I dont arrive until the 29th but if you are still going to be there, let me know where you are staying and I'll look you up.
In terms of good places to have a beer, there are plenty. It really depends on how "friendly" you want it to be ,if you catch my drift.
I would avoid Pat-pong as it can be a little dangerous there on your own, but Nana plaza near Nana BTS station would be a good place to start. Even if you are just after clean fun and a bit of a chat, it is still a great , vibrant atmosphere. Jusy avoid the upper levels of this multi-level "adult entertainment venue" as it can get a liitle perplexing to pick the orientation of the staff there.
Beers will be more expensive there than other places, still cheaper than nightclubs at home but it is a great place to people watch and there will be alot of other single young people there that you can chat to that will give you tips on other places to go.

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