Ultimately, does anyone really ever set out to do real estate as a minor part of their life's ambitions and succeed in it as a side hustle that they spend a carefully limited amount of their time and energy on?

You select your end, what the ultimate destination is.

I had a WIDE range of quotes for my building, but I ultimately winded up using Hemlane for the quote as they had the best price and coverage. 

I still think this is what's bound to happen ultimately.

However, if this is during an economic downturn when default would likely happen, there might be no equity in the house for the original seller, and I can't see how a seller would be comfortable being ultimately responsible for a mortgage that might last 20-30 years.

Of course, it ultimately depends on your available funds, short/long-term goals, etc. 

My ultimate goal is of course make a bigger profit.

Ultimately you need to put in what the masses will like and not what you like.I do a lot of contemporary designed homes and some of them get white shaker cabinets while others get grey shaker or some other contemporary style and color.

So, I have no idea how much money I owe for 2023&2024, how much money is actually mine, how to take advantage of tax deductions/credits/RE professional Status/ renovation costs/perform a cost segregation, if I really need a wealth manager at this point and how to take out my retirement investment and move it to a mutual fund I run independently.My ultimate goal: create systems for my corps to run smoothly and optimize business-related expenses,  keep my books up-to-date for both corps so I know my input/output, pay quarterly taxes throughout the year, give myself a modest monthly income and  continue to preserve/build wealth and grow my RE PORTFOLIO!

My ultimate goal is cash flow to be able to quit my job (self-employed) and focus on real estate full-time.