I do symphasise. I too live in Devonshire ( the Park Lane of South London ) . I had a car up to recently. I always parked at bottom of Ewelme Rd as much safer and never had any problem in 22 years. However I do appreciate you are a long way from ER and need to park outside your property.
Not sure what you can do. Un less someone witnesses the incident and takes details , but if in the early hours unlikely.
Sorry cannot be more helpful but hope you have no more problems