Plumbers

At what time is it considered that you are paying other peoples bills?  We have a blocked drain which is now unblocked at a cost of $330 but it will now stay unblocked for another 5 years, as we had this particular spot cleared 5 years ago.  It seems to me the new owner owes us a pro-rata amount. We have cleared their drains for 4 years and 9 months. It's the Silver Birch that is the culprit and it was here before we arrived.  And in the end either it had to go or we had to go.  It spits tiny seeds that invade every part of the house, particularly in summer with the air con running.  It drops half a metre of leaves in autumn. I need to fill the green bin three times to clear them. It's roots run deep and invade our drains and its branches are a convenient bat roost.  The bat who sat in the scat is here every night.  Each morning I have to clean off a ton o of guano from the fence and paths. 

One of the Mario Bros