If you're staying for a couple of days, it's worth cultivating a regular moto driver (many guesthouses have a bunch of reputable guys).
Saves hassle, and can be great if you strike up a rapport, even better if they speak a bit of English.
Pay 2000 riel per journey (maybe 3000 at 3am), or negotiate a day rate.
Plus if you're planning on being out late, having a moto driver you trust who you can ring up on a mobile is worth the extra peace of mind.
Ask your guesthouse owner
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