First you need to learn to separate the following:Maintenance: usually things related to wear & tear or tenant damage.Repairs: usually broken items like doors & windows, caused by tenant or nature.Capital Improvements: usually expensive things that wear out: hot water tanks, furnaces, roofs, etc.The seller is correct that Repairs & Capital Improvement items should not be a factor for awhile (ALWAYS get your own inspection to confirm).

Do you remove the roof from your houses because roofs do not prevent flooding?

if there are 10 interior cosmetic violations opposed to a roof repair violation I'd imagine one would be more motivated than the other.  

Roof, HVAC, sewer, etc.Has the property been poorly managed?

You send mailers and attached to a mailer is a sample of your latest baby-cow rack of tenderness.You send all these vegans a mailer asking them to buy your baby-cow burgers.Half of your mailers get returned.Now, do you really think the accuracy of any skip trace company is going to make a difference getting any of your burgers sold?

For example, ask about typical costs for HVAC repairs, plumbing issues, or roof work.- Use Historical Data: If the seller has accurate financials, their expense data can be invaluable.

The owner also needs to save for big ticket items that may need to be replaced every 10 or 20 years such as AC, hot water heater, furnace, roof.  

Sure enough the rehab ran over budget (we had a large contingency that was used up -- some due to contractor malfeasance, some due to pulling the trigger on big repairs like a new roof) and the revenues were right around expectations, maybe slightly below.  

Everything seems to work as is for the time being, but I'm budgeting for the roof and furnace replacement in the near future. 

Fees are through the roof.