Price materials and labor cost will depend on how large of scope of work but a good company is going to be around 3500 a week plus cost of over head we also pay 30% tax on our income also like you guys but if you anticipate 4 week rehab well be ready for minimum of 14k in labor +14knis low end in my opinion... now I'm currently eating my lunch on a rehab from hell but it's gonna be a work of art from where it came from... this was the worst of the worst in my career water damage to all structural raised the roof on a horrible addition and did it correctly. 

It is a huge ticket item and can eat ~30-40% of my reno budget.Today I did a walk through with plumbers and contractors.

While a business owner's job is primarily to focus on revenue, you also have to make a basic effort to control expenses and keep things from eating up 1,2,3,4% or more of gross income.

I realized I much preferred to eat dinner at home, where I would be satisfied and not still hungry afterwards.With that said, I'd love to purchase your book!

On the topic of the Data Center: To shed a little information without revealing too much: I would beware putting too many of your eggs in that colossal data center basket.  

Once you move, you'll have to hire someone to manage it for you, which will eat into the income.

But keep in mind that things like closing costs (where you have to close twice - once to buy the flip and once to sell it) may eat up $10k of that profit before you pick up a hammer to repair something.

Obviously a high interest rate could eat into your investment.

For those 2019 properties, even if they have fixed rate, long term loans, when the loan transitions from Interest Only to Amortizing, that can eat a lot of cash flow.  

If it's your mom's next egg, you don't want to take risk that is not fully educated.