They reneged on finishing their funding which led to our closure. 

I ended up purchasing the condo and just finished renovating it over the last week.

At the moment, this house loses me about $1,000/month with my living in it, but once the basement is finished, which will include a walkout and kitchen, and my interest rate matures later this year, this home will bring in about $287/month without me living in it.Soon to be 5 bedrooms, 5 bathrooms, 3,822 finished square feet.

Soon to be 5 bedrooms, 5 bathrooms, 3,822 finished square feet.

I have two other homes; however, I sold one and when I finish the other I will sell it so that I can clear out my personal debt.

You need to develop a Scope Of Work that is precise and then start getting prices for all the work.Once you have that magic number, then you will add that to the cost you pay for the house, along with any other fees or expenses...Then look at finished Comps (get a Realtor like @Chris Ayars said) and see if you will make any money......

An outside contractor would probably finish it in 2 months and allow me to rent it several months sooner than if I built it in my free time. 

So I'm a 22 year old investor just starting out I started flipping my first house this year and I plan on being finished with it in a month or two and I've been looking at how to invest my profits for the most return on investment, I'm leaning towards seller financing vacant properties and master lease options but I want to get another opinion, so if anyone has any suggestions I'd be glad to hear it.ps.

Not sure of the intricacies of that.I finished a detached ADU in 2020.

It will probably take 2-3 from start to finish unless it goes quick.