Costs ran significantly over on both of these items and not being in the area it was not possible for me to add my experience in renovations to lowering them. 

Investment Info:

Single-family residence buy & hold investment.

Purchase price: $179,000

Cash invested: $25,000

Sale price: $500,000

Replaced windows, remodeled kitchen and bathroom, replaced...

You need to do testing before renovation and after to confirm that all mold remediation was either done by a company if the area is still there.

This will usually lead you directly to low barrier stagnant markets where the cash flow represented in your spreadsheet does not transfer to reality and the most of the equity is "paper equity" because you will never see it materialize yet many look at completing the BRRRR as the ultimate success.I recognize I am using some assumptions but let's assume you have $100k to invest and purchase and renovate a home in MARKET A for $400K but once renovated the home is worth $500K.

After investing $47,000 in thoughtful renovations, we transformed the property, enhancing both its functionality and appeal.

I flipped a condo in Washington DC and used the forced equity to purchase a buy, renovate, and hold property in Richmond.

Is there any way to use the equity in my current property to put towards the new property, or am i basically stuck selling the duplex and rolling it into the larger 6 unit rental?

Larger families, remote workers, or investors could see it as ideal, especially if local schools or amenities like parks, dining, or entertainment are strong.

What you see staying on the market longer are homes that are not renovated asking top dollar or above 

In my personal opinion the seller should be aware of the market value of there home both before and after renovations and choose to sell to a wholesaler based on the convenience, timeline, inability to sell the house on the market, etc.