I was recently reading a email about wholesaleing bank owned/properties.

Hey Clint welcome to BP, There are only a select few wholesalers that work the Lake County area...and from experience there are a 1-2 that you should very much steer clear of. 

Is this the seller's agent or wholesaler that is telling you this?

Looking at the REIA options in Seattle there are a lot of good options however they are primary focused on Wholesalers and Flipping which is not true Real Estate Investing but a RE Business.

Are there any specific rules and guidelines or restrictions for wholesale housing in Detroit or metro areas?

I am most interested in wholesale right now but am open to flipping.

I'll be using traditional financing for my first few, will a wholesaler still sell to me in general or are they cash only buyers?

Im a new wholesaler.

We try to be the full service for the real estate investor/landlord as we handle closings (regular, wholesale, creative real estate deals), evictions, foreclosures, LLC formation, draft leases/contracts, tax redemption matters, etc.  

The people you sell those wholesale deals to are the Investors.You will become an Investor when you are able to use your Wholesaling proceeds to actually invest in something that also starts paying for itself.