Thought it could be of huge value as I made this purely from needing it myself when I did my first fix and flip project.

It should be broken down by phase and/or service. $90k may be a bit high but don't expect to pay $10k.

If all parties were agreeable (and would likely agree on an interest rate lower than a bank's would be), with $0 down his monthly payment would jump $300-$500, but now he would be building equity in the property.Is there anything else I should tell him or anything I am missing?

However, this varies by location and may not be immediate.

My other one does really well as a STR, doing double or sometimes 2.5x what it will do as a LTR.

Rehab them to be all in of 140k.

If you want it to be a business name, then I recommend you set up an LLC, transfer ownership to the LLC, and then change your leases to match the new owner name.What is your reasoning?

Being able to do your own renovations and improvements will give you a serious advantage when house hacking or even working on your own projects.Akron has some solid real estate opportunities, especially for house hacking in multi-family homes.

Im able to find great cash flow here and over the last 5 years we have seen appreciaiotn play as well. 

That covered not only the liability from my property to me but also the liability from me to the properties.The umbrella insurers want to be insurance of last resort so will have you beef up liability on your rent properties.