Anywhere close to a BTS station ideally, towards the center. Asoke BTS station is what most people consider the center of Sukhumvit, but remember Bangkok is huge so there's a ton of different areas with centers.
This is the hotel I usually like to stay at when I travel back to Bangkok. Sukumvit 24 has a bunch of hotels though all up and down the soi, depending on your budget.
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34%2C
*****
39%2C
*****
71%2C
*****
81%2C
*****
39%2C
*****
48%2C
*****
64%2C
*****
64%2C
*****
19%2C
*****
68%2C
*****
51%2C
*****
69%2C
*****
88%2C
*****
42%2C
*****
58%2C
*****
47%2C
*****
15%2C
*****
34%2C
*****
35%2C
*****
61%2C
*****
27%2C
*****
11%2C
*****
70%2C
*****
59%2C
*****
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