Buying preforeclosures to flip

[Devin Bost]

I've been aggressively studying how to successfully buy, rehab, and flip (aka "redevelop") residential properties, and I'm currently working on my marketing strategy. I've been investigating the idea of looking for off-market pre-foreclosure properties specifically, and I'm wondering if anyone has any tips or stories "from the trenches" regarding how to do this successfully and how to avoid any critical pitfalls. 

I'd also like to know about things like:

• How motivated are the sellers typically (especially in comparison to other types of distressed seller situations)? 
• How easy is it to find motivated pre-foreclosure sellers (especially in comparison to other types of distressed seller situations)?
• Are there legal complications that can occur?
• How sensitive do you need to be with the timing of the sale, such as when foreclosure proceedings are starting or about to start?
• Are there additional risks that are more common with these types of properties?
• How often are the sellers very emotional and hard to deal with?

Any guidance would be much appreciated.