Also, I'm sure several lenders will respond to this thread and offer to work this deal. 

Would it be best to start an LLC or sCorp in CA and deal with the astronomical annual fees?

I think in this instance it would be better to do one investor per deal rather than doing it as a fund and hypothecate each deal as it comes along. 

Quote from @Leeling Chew: Documentation probably isn't that big of a deal.

Borrowing against your paid off house without an income puts way too much pressure on the success of whatever deal/project you decide to pursue. 

In my experience, a successful BRRRR typically comes down to two main things: finding a good deal and managing an efficient renovation.

I would argue that there's intangible value in every deal!

As a beginner investor based in the Seattle metro area, I'm eager to learn from your experiences and share my journey as I get started in this field.My current strategy is to focus on live-and-flip for the first three deals (looking for my second deal) to gain hands-on experience while building equity and learning the ins and outs of renovation and the local market. 

Depending on the seller, you may sweeten the deal, by letting them know that they don't immediately need to cash out, or can partly cash out.

You can use a SQ FT format to guess rehab but that is only good to initially look at a deal.