HELP: Valuation for 4 Unit Building purchased 2 Months Ago

[Scott Bartlett]

We purchased our first 4 Unit Building after a successful Triplex property. We came across a property with the ability to financing using seller financing, and noticed that the property was severely mismanaged and low rents. So we seen a good valuation here:

I've included a screenshot of how I came up to our valuation:

We are planning on raising rents again once some capital expenditures are completed and after some vacancies to paint and update the units with new flooring and etc.

So if my figures are correct, by raising our rents and NOI, our valuation of the building has increased from $110,000 to $148,290 and then eventually $193,760?

This is really the first time we have started investing in Multifamily buildings and honestly never bothered with CapRates or Valuation (SFH are pretty simple, COMPS). I just want to make sure my figures appear to be correct and our beliefs are correct that we found a decent deal.

This method also allows us to track our progress on "paper". Any issues with my calculations?