Calculating Rehab from only an outside look

[Bryan Berrios]

How do people estimate rehab costs when driving for dollars for off market properties when all you ever see is the outside? Like if a property is vacant with out of state owners? You obviously can see the state of the exterior but you don't know if there's messed up plumbing or if it's trashed inside. For example, how does a wholesaler see a distressed property and find the info for an accurate rehab estimate to be able to present it to an investor?