I've seen comps that were blatantly incorrect, claims of new roofs/furnace/etc that were not true, etc. 

One thing a good inspector will have is moisture detector, and temperature sensing equipment, that could tell you if something is leaking somewhere. 

My wife does a video walk through every six months-long term tenants annually-she looks under sinks, checks alarms, looks for leaks etc.

But now the kitchen faucet in Unit 2 is leaking and needs to be replaced. 

Either or works Well just use this as a simple example 24 Unit apartment Complex ( B-  or C +  type  property Purchase Price - 1,920,000 ( $80k Per Unit ) may be low in this market Down payment - 25% = $480,000 Rehab - $ 6,500 per Unit ( some units  more than others ) = $ 156,000Common Rehab - Water Heater , laundry room if it has one , Paint of building , landscaping , windows , parking lot  , roof ( 10k - 70k ) This ranges a lot depending on the property Closing cost - 20-30k tax - 7,000 / year insurance - 12,000 ( wind n hail , general , fire  ) / per year Property Management ( 10 % ) = 2,160 / per month vacancy - 10 % = $ 2,160 per month Cap X ( fridge , window , curtains , doors , paint , roof , pavement ) - 1,080 / per month Landscaping - $ 800 per month simple repairs - $ 500 -900 per month common area electric - $ 300 per month Mortgage $ 7,500 ( 30 year amortization  , 4.75 % rate  ) Income - $900 per unit = $21,600 , this varies based on area . 

If the tanks leaked, remediation and cleanup will have to be done, and the property readings will have to be under maximum allowable percentages of contaminates for a certain period of time before the property can be re utilized.As to the asking price, either the seller doesn’t really want to sell, the seller wants to see if he can find a sucker; or possibly the value of the land for future development is much more valuable than the existing use.But assuming that the latter is not the case, what is it that attracts you to a deal priced over twice market value with a possible environmental problem to boot?

You might have foundation, roof, HVAC, and  WDI inspections as those are typically free or low costs.   

For example that Hospital that got built in 3 days, from what I read, it leaked, and there were issues staffing it.

I also do a lot of the rehab (except, roofing, HVAC, electrical, and heavy plumbing).

Particularly recent upgrades to the structure, such as a brand new roof, etc.