Don’t rely on other people’s estimates for rehab, projected investment return, ARV, etc.

That rule is just to give you an idea of whether to do further analysis, it should not be relied upon for purchase decisions.

Do not rely on it for legal advice.

Plenty of money for dog food pet care cigarettes and beer but nothing for rent so they rely on Uncle Sam ( aka Johnny tax payer)  

Don't rely on due diligence of working with a licensed realtor.

If you ended up in a situation where you had to move out early, the bank would rely on "intent" to decide to go after you or not.

Firstly at the end of the day it's the AHJ's (inspectors) call - however from my experience they usually rely on what are referred to 'prescriptive' methods for design (ie: IRC, span tables for joist sizing, tables that dictate minimum design requirements, etc) and if those prescriptive requirements do not meet an application, that's when often they will either require an engineer, or give some direction if they are comfortable.When using a sister to an existing framing member, the capacity of the new member should be evaluated but also how it is attached to the existing, as a shearing failure of the screws/lags can occur. 

If you look at the few pro's that rise to the top, they earn a very good income, are highly organized, rely on systems and teams and will typically turn their business phone off after they leave the office, so they actually have a life.Wholesale is basically the same in terms of lifestyle and in terms of financial outcome - only a very small portion really succeeds. it is probably one of the most difficult roles to pull off successfully, because you have to know so much about so many things, from construction estimates, to property values, negotiations, marketing etc  

I need to be able to rely on my own expertise.

I rely on prompt payment of rent because I have to pay the mortgage.