It sounds like this guy is trying to make some money by providing information that you can freely access here on Bigger Pockets.If you have no cash for down payment and credit is not perfect then yes, wholesaling may be a great solution.Always, always double check with the folks here when paying any sort of money out-of-pocket for tutoring, coaches, classes, courses, etc.  

IN our market on the West coast many times its frowned upon to double end deals..

It's the rare deal or situation where an assignment or double close would work for me.

Most REO's will not allow you to assign the contract, which means you will need to conduct a double close/simultaneous escrow. 

Seattle right now is experiencing strong job growth, large companies are doubling down, and a number of decent areas (west seattle, magnolia, ballard) are really improving another notch. 

A reverse exchange could be even more powerful allowing you to capture double equity while picking your perfect next purchase.

It also needs some rehab, and I wasn't 100% certain how I was going to handle it (probably using more cash which would have more than doubled the down payment, or do a cash-out refinance against some other property -- not something I really considered).Here are the ideas I have had since; any would work for this deal, though some are better than others:Use crowd-funding for the repairsFind a rehab loan to include purchase price and rehabAsk seller to carry a 2nd to cover the rehabAsk seller to finance entire sale and use cash for rehabUse HELOC to make a cash offer and for the repairsFind a partner in Florida who has cash but no credit; split DP and rehab costs appropriatelyUse hard money for purchase/rehabThe HELOC actually makes the most sense.

Is it best to have an assignment of contract fee as opposed to a double close?

So IRR or annual addition to net worth should be your cash flow, mtg buydown, appreciation, personal tax savings, lets say it  is $23,000 the first year, and this number will go up every year but just use the 23k X 30 years=$690,000 then add the  value of your paid for property, lets say it doubles to $650,000 add it up =$1.34 million, subtract your recaptured gains and you should be around a million.  

Buying from wholesalers isn't such a difficult process if the wholesaler knows their stuff and you have a closing attorney who is familiar with double closings.