It would be more ideal if you had or can find an investor friendly agent there to rep you as the buyer to ask all the questions or know what questions to ask for you to figure out more about all four units. 

@Kelsey Vander Meuleni am assuming this is not the answer you want but why not just hire a property manager?

It sounds like you would benefit from hiring a real estate agent to represent you.

Partner can or you can hire a pm2) property has not enough equity to heloc or sell at return but prospective partner is willing to buy into the partnership. 3) even if the partnership ends up being short lived, there is an opportunity for further appreciation in that span.4) you fear the risk of a poor season.  

But the right home or group of homes can enable you to hire managers and staff to run things FOR you.

I have hired a property manager to manage the property  who will provide me with the 1099.

If he hates managing he needs to hire that out and then use the extra time to start flipping.

When I started, I hired an attorney to handle my evictions.

When I used to be a tenant, my landlord had it in the lease that at the end of the lease for move out, the tenant has to hire a professional to clean the gutter, clean the fireplace, clean the carpet, etc.

Simple things like this are why you hire a realtor.