Quote from @David Tiefenthaler: Brandon is a great teacher and a good person, but that book teaches methods that are not good for investors and are more likely to get you in trouble.

I would also suggest you reach out to someone who has experience in the BRRR method of investing.

It sounds like you have already defined your investment strategy using the BRRRR method.

Using the BRRRR method, you can actively increase the property's value, which is then reflected in a new appraisal when you refinance.

Changing Your Accounting MethodGenerally, you must get IRS approval to change your method of accounting.

I plan to do the BRRRR method (They are in their early 50's so they have about 15 years or so before we would want to sell or I buy them out of their properties for retirement) .Thank you in advance for any advice! 

If you have a property and are looking for investors, what are some methods you can use to find genuine investors?

By end of year I am estimated to have saved 45K.I am looking for alternatives to purchase more doors specifically the BRRRR method.  

That's a method of borrowing money to borrow money, which is how people over-leverage and get themselves into trouble.You were fortunate enough to jump into the market when everything worked in your favor.

All you need to do is find a lender that understands and specializes in working with BRRRR method investors that flip at scale and at speed.