Wait a minute! What do you mean that the LL did not give you a chance to find your own plumber, or fix it yourself? YOU said " I asked him to send the plumber "! Apparently, you didn't ask WHO was going to pay for the plumber. If you had, and the LL said "you", you may have decided to buy a plunger and/or some drain cleaner, and do it yourself. The cost is on you.