The method of payment doesn't really matter - what's important is that it is tracked in Schedule K-1 and reported to IRS. ...

this is old  tried and true method of simply having you pay them to get credit cards .. there is no need to pay for this service.. unless you want to of course.. there is no magic bullet ut there that is going to give you credit and financing unless you actually qualify for it.But zero interest credit cards are used by some to do rehab and then pay them off issue is though your fico score drops like a rock the second you take on all these CC.Also starting out there is zero chance of getting any kind of business line of Credit that is unsecured.

The method I mentioned above of refinancing notes, try to calculate a yield on buying a discounted note and 30 minutes later refinancing it at the UBP!

This is technically a method of buying/selling real estate, which is illegal without a real estate or law license. 

DSCR is often selected for the BRRRR method because it flexible seasoning.

Nathan's search method usually works, but I use what Google suggests: '<search item> site:www.biggerpockets.com' (without the single quotes on the Google search bar.) 

Also, is there any method you know of to shorten the cash cycle?

This method allows you to take some of the profit tax free and indefinitely defer the rest of tax, using it to purchase larger, nicer property/properties in areas with better cash flow potential.

If I go with the BRRR strategy would love to hear some tips on how to successfully manage the rehab remotely. if you have money you could potentially lose to learn quicker start with the BRRRR method.

If you are seen to be using this for investments, then you will find it hard to get another FHA loan, making this method difficult to scale, but good when you are getting started.