8 Unit Full Rehab - Initial Offer - Help???

[Silenceux Francois]

Hello Everyone,

I located a 8 unit apartment complex in need of a full rehab. Listing prices is at $200,000.  Each unit is a 2/1 and the average rent for that area is $800. I contacted the listing agent and complex has been vacant for the past 2-3 years. Some units has copper missing and slight water damage. How do I assess the true value to make my initial offer?