Bro, Kovan only these 2 budget hotels at the moment. Unless u are looking for those damn budget hotels along Geylang Rd which are associated with high risk.
For H81 with $20/2hrs rate, u could perhaps consider
Dickson H81(quite new) off Jalan Bear,
Elegance H81(quite new) off Foch Rd,
Violet H81 &
Lavender H81(old with lousy air-con) both off Lavender St.