It seem like majority of parents still bring their baby / children to nearest polyclinic for jabs and development test mainly because it is free of charge aka fully subsidy.
Do you know that wef 1 Nov 2020, Singaporean baby / children can get FREE jabs and development test at any of CHAS GPs also?  (Link)

If you do not stay walking distance from any of the Polyclinic, this is definitely more convenience for you (You can search for your nearest CHAS GPs here). No application is required to enjoy this. Just walk in / book an appointment with the CHAS GPs will do.