maybe do something on the rubbish that she hang on fence...
cut some holes on the bag everytime she hang it on fence and let the rubbish fall onto her floor and she will feel hassle to clean it from floor... cruel ways but may efficient... unless she also dont want to clean the floor, then nothing we can do with such neighbour that wont take care the house AT ALL... report to landlord that she "torturing" his/her house and landlord may giving she trouble...

i dont think Majilis Perbandaran will help much on this issues since is no an serious cases...
the most they give advice to her only and no legal actions will perform...
unless the house located at gated and guarded community... i believe someone did something wrong to the community and may able block their access tag to hassle them when going back their home...