be it highrise or landed, there's actually no dedicated or insistence from Authorities to impose car washing facility if i'm not mistaken.

the landed homes do have a tap point which is meant more towards watering the landscape instead.

however, thoughtful developers do tend to consider this and incorporate into their design requirements. hence some highrises do have these features while some do not.

if you are particular about your car cleanliness, you may wish to sign up for those more professional car detailing shops which provides dedicated and attentive cleaning?