i went on a solo trip to KL & Sing a few days after i turned 18.(3 years ago) it was my parents "welcome to independence" trip for me lol. had no problems checking into my hotel in Sing. stayed at a boutique hotel in china town.

the only minor problem i encountered was leaving KL. for whatever reason the customs officer grilled me for a good 5-10 min about what i was doing in MY where i was headed. he was really curious as to why i was traveling solo and why my parents weren't with me even though i was over 18. apparently he didn't believe that the pic in my passport was me since it was issued when i was 12 or 13 years old.