Our contractor also got this in writing from the gas company that there was no trace of gas leakage or anything.This neighbor also has caused similar issues for the other adjacent house to his and a couple of other houses in the neighborhood.Anyway, I wonder what you guys would do in a similar situation?

Our utility company which covers Nest development office suggests better insulation, furnace and air duct leakage as most household, apartments have an appreciable leakage issue.

I had a sewer line collapse in my duplex last fall - the old clay pipe collapsed, causing black water leakage into my basement and I called in Roto Rooter for an emergency containment and restoration since I had tenants living in one half and was actively showing the other half.

In order to stop the leakage of sewage, I had to fix the problem myself by hiring a plumber to excavate the pole and clean up the damage. 

Let me know I can help any further.Basement Requirements:15.12.540 - Basement space prohibited as habitable room, dwelling unit.No basement space shall be used as a habitable room or dwelling unit unless:A.The floor and walls are impervious to leakage of underground and surface runoff water and are insulated against dampness.B.The total of window area in each room is equal to at least the minimum window area sizes as required by Article IX of this chapter and is located entirely above the grade of the ground adjoining such window area.C.The total of openable window area in each room is equal to at least the minimum as required under Article IX of this chapter, except where there is supplied some other device affording adequate ventilation and approved by the housing inspector.D.There are no pipes, ducts or other obstructions less than six feet six inches above the floor level.E.All furnaces or other heating facilities are so located, insulated and separated from living areas by fireproof partitions or walls necessary pursuant to regulations of the fire director, so that the same do not constitute an undue hazard to the safety and health of the occupants.F.There is a second means of egress conforming to the requirements of Section 15.12.270 of this chapter.G.Basement space which shall be used as a habitable room or dwelling unit must conform to all provisions of this chapter and all other applicable ordinances.

This is also why I always preach that annual walk through inspections focus on checking all potential areas for ANY possible small signs of leakage.

Forget the bilco doors and water leakage.

I recently replaced the toilet and the plumber tested for leakages and none was found.

It appears the shingles are drooping notably at the ends of the runs in certain areas, possibly hiding at least one layer of old shingles.Your interior pics do not show any concerning areas of leakage or mold.

., it seems like a 1031 exchange would one of the better methods for building a bigger portfolio while minimizing tax leakage, but it doesnt seem like Japan has such a tax deferment scheme with respect to investment property (but there is such a scheme for self-use residential property in Japan).