The Service Charge Dispute Guide – Educate yourself with factsheets, a case law library and jargon explained:
http://www.servicechargedisputeguide.info/category/guide-to-leasehold-law/overview-of-the-landlord-and-tenant-act-1985/page/2/
The Leasehold Advisory Service – Events, advice guides and tribunal decisions:
Islington Leaseholder’s Association – Our sister organisation in Islington:
http://www.ila.org.uk/