Artificial inaccuracy for privacy reasons (hide street address)

I have a geofield geocoded from an address field.

The address field has an option (via another field) to have the city and zipcode public, but the street and number private, for privacy reasons. The idea is to prevent uninvited guests, or e.g. burglary.

However, the geofield coordinates (e.g. shown on a map) reveal the exact location, so it would be easy to guess the street address.

Is there a way to either
- geocode only the zip and city, but not the street address, OR
- geocode the exact street address coordinates, but then only display approximate coordinates, e.g. with a random vector added?