Personally, if the pipe fittings were not leaking, and did not show signs of significant corrosion, then I would probably leave them alone until there was an issue.

No leaks from roof or in basement.

It is required to have a building permit/inspection and hire licensed professionals for Electrical, Mechanical, Plumbing, and structural engineering for load bearing, gas line work, and septic systems. 

Deck is falling down (covered by HOA) but has resulted in an ongoing ceiling foyer leak.

If they find the tank has leaked the costs go up big time .

-Question: What are some smart financing options to still fix the leak knowing that I’ll probably sell in the near future?

They are made of thicker plastic, tougher, and odor/juices won't leak through.

Sometime after the inspection a water leak coming from the neighbors home caused damages to the property.

This is causing water leaks.

Inspecting revealed a water leak from the second floor, above the garage, that shorted the light.