Stumbled upon a brand new hotel on Sukhumvit Soi 4 last month, so if you like "clean, secure, quiet, & new" then this is the place.
Called DI Place, has about 20 rooms, ranging from 770 Bht to 880 Bht depending on size & features in the room. It also does short time at 300 Bht.
Free WIFI in reception, and internet PC available for small charge.
To find, walk along Soi 4 from BTS end, past Nana Plaza, past Hillary2 bar on left, then turn left as you reach the Tavern, down a small Soi (unofficially named, Scott Place)
The GPS co-ordinates are N13.73978 E100.55336