Realnet don't look after their tenants!

Before I signed a lease agreement as well as the inspection, Realnet promised that they will fix the roof outside which had holes in. We could not sit outside as the roof was leaking. 5 months went by and nothing was still done, this was after numerous calls and emails we have sent them, they promised to fix it. But nothing! I cancelled the contract as the Landlord did not fulfill their duties. Realnet made sure that after this cancelation we won't even get half our deposit back! And even denying the fact that the Landlord made breach of contract by fulfilling their duties. This was the worst experience ever!