You can find reliable agents for your home buying, selling or renting needs here: https://www.propertyguru.com.sg/property-agent-directory
Do note there are strict HDB rules and regulations that you must adhere to when renting out your room. You must seek HDB's approval before you rent out your bedrooms or when you renew the tenancy. The minimum rental period for each tenant must be 6 months per application. You are not allowed to rent out your bedrooms on a short-term basis, as it may disrupt the living environment and pose security concerns for our residents. You may refer to HDB's link here: https://www.hdb.gov.sg/cs/infoweb/residential/renting-out-a-flat-bedroom/renting-out-your-bedroom/regulations-for-renting-out-bedrooms
Hope this answers your question.
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