I always suggest your property have at least $500 in residual income after mortgage taxes insurance and property management.

I have not closely inspected carpet and ducts for damages or residue . 

Individual stores don’t have residual values per se.

According to 50% of the rent receivable less TDS if any, over the period of 84 months or residual lease / rent agreement period whichever is lower subject to a maximum of Rs. 400 Lakhs.

If you have any ruptures, you will get some leaking even with the mains off due to the residual water and pressure in the pipes.

The issue is not that there is an underground tank its if the tank leaks and has residual oil on the property.   

My experience is that most smokers these days smoke outside, and residual smoke on their clothes has no effect on the unit.

Should I have the house inspected to ensure that there is not any residue, smell, mold, etc that may be due to the pot being grown in the basement?  

That's actually a terrible lease, you paid for that lower residual.

A friend here in Florida is getting ripped off by his property management company after moving out claiming a tiny piece of scotch residue on the fridge door is gonna cost $400 to replace the whole door and ridiculous other items.What’s the proper way to challenge these charges and maybe even proceed with a formal complaint?