The homeowners were attached to their home, and asked to interview my brother and I before sale.

If you're just starting to look at deal and trying to figure out your footage it will be a good idea to start interviewing agents to see which one is oriented towards the same market you like and know how to analyze the deals properly. 

Phone interview all of the options, ask questions about their process, if they manage in the particular area you are buying, fees, and get a sense if you can work with this person. 

If you don't, interview some and find one, when you have someone good and creative, they can be worth their weight in gold in helping give you numbers for different options, then you have some facts to base your decision off of!

@Krista Porter - Interview, like you would anyone else!

Other factors include location, employment, size of town/city and lastly interview property managers.  

I must admit that your company is on my short list to interview when the time is right.

Interview 3-5 folks in every field (lender, broker, roofer, etc.) then make a selection.2) you don’t need a General Contractor, you need skilled professionals

I've listen to many podcasts where new investors are interviewed and they speak about how the started with no money and yet have been able to amass 20-30 units in the first year or two.

Try yelp and hit up a few and interview them.