If you were building it with cash and had $450K to play with, I would look at buying 1 or 2 more duplexes for $900K at 50% or 25% down and you are probably making more cashflow and you are building equity on multiple properties instead of just the 1.

By understanding what they want and need, you can come up with answers that work for everyone.When negotiating a real estate deal, each seller is different, and their professionalism, tastes, and goals all play a big part in how the deal turns out.After thinking about my trip, I've learned that the best way to negotiate is to know what questions to ask and then listen to the answers.

If you're serious about this, you should definitely consult an attorney.I am not one, but here are some things I've learned from playing around with these types of things:--Trusts are excellent vehicles for anonymity--You can hire a professional fiduciary (like an attorney) to act as trustee so the public contact is not easily affiliated with you. 

You made a generous offer, and it seems they are playing a game of racketeering. 

Don't focus on how you'll behave during an after-game press conference as a WNBA star when you haven't even played your first pickup game.Buy a property, learn how to manage it well, and see if this is the right investment vehicle for you.

Then there was the peyote church leader who seemed really nice and cool at first but then started growing mushrooms and peyote in his closet, and when I went out of town he hosted all night bonfire peyote parties in the yard playing bongos all night, then stabbed another house mate who came home hammered drunk and asked the peyote church parishioners to be quiet at 4am or so and they both ended up in jail and I had to evict them both while they were in jail.

The agency of selection will dictate if commissions come into play or not. 

@Abigail Lipson if you want actual assistance, then share what you've done so far and ask if you've missed anything or made incorrect assumptions.To just ask for general assistance or for someone to share their evaluation criteria makes you appear lazy and wanting other people to do your work for you.One of our company's mantras comes into play here, "if you don't ask the right questions, you won't get the right answer".Please ask better, more specific questions, so we can better assist you:)

As for renting, going cash flow negative isn't great, and your home isn't likely to appreciate as fast as it would if it was a single family home, so holding with hopes of increasing appreciation may be a verrrry slow play, but if you can afford to hold, having a tenant pay down your mortgage is an additional great benefit to real estate investing. 

There are so many factors that go into play on real estate that you mention its all about perspective and investment strategy.