Your Homeowners' or Condominium Association can explore taking legal action against Members who violate Restrictive Covenants or Condominium Rules.
Lawbreakers can be reported to City Code Enforcement and / or to the Police.
Illegally parked vehicles can be reported to the Police.
Child Endangerment can be reported to Family Services.
The Media (Newspapers / TV) may have an interest in "Obnoxious Neighbors".
See an Attorney for Legal Advice.