Depends on what you are analyzing.Do I believe sellers pro-forma numbers??

I asked for the pro-forma, plugged in the numbers and it failed miserably.

@Lou R.There are many possible reasons:NOI numbers in the pro forma are likely rosy ... a thorough analysis could tell a quite different story;There may be other liens or defects in title on the property;The building is facing functional obsolescence or is carrying too much deferred maintenance;There is a forthcoming change in the local economy (major employer downsizing/leaving) or neighbourhood (redevelopment, highway or manufacturing being built close-by);The list goes on, but it always comes down to a lack of value in the proposition: either there is a significant problem with the business or the asset which makes the acquisition costs unreasonable.Now, sometimes this can be a good thing - if you are certain you have identified the issue(s) and know you can effective remedy them at a cost which the business could afford, you may have yourself a deal.  

Pro forma Cap Rate 4.8, Purchase Cap Rate 5.6%The only reason I am a little stuck at wanting to go a little deeper into this deal is because, the area is decent for better rent, and I believe the apartments are all under value in terms amount...

You should definitely charge interest on this, and if they could qualify for this loan form a bank, they might as well just buy it from you outright.

Most pro-formas that you will be presented when purchasing investment property will typically have a 20% down and 80% loan to value scenario.Can you put less down the 20%?

Investors will find those services more valuable and want to form a relationship with you

I would tend to look at it as a long term investment.If you are looking at that investment as an investment that is just the start of primary income, I would recommend that you try to form a Partnership and buy in-town apartments with a positive cash flow on day 1. 

You pitching a 3.41% pro forma with a negative cash flow as a 'attention investor special' on loopnet might not get the amount of traffic you are hoping for.And lets say your property is a solid B property after your investment.

Depending on what you have to offer there may be opportunity to form a long term relationship.