@Russell Brazil nailed it, not much to add.

@Tobey Porter nailed it.

@David Ounanian hit the nail on the head with his comments that you can still see good cash flow and a more "stable" tenant pool. 

The more you can nail down your focus and avoid shiny objects, the better!

However, we have had some trouble nailing down exactly how we should be analyzing these larger deals, as many of them contain some properties that are very old and run down with some solid ones in there as well.

I have a client looking to do a 50k rehab on a home, and we are having difficulty nailing down a good contractor for the job.  

I think @Katie Magoun nailed it!

Now, if you want to gamble a bit 'cause it's really a nice place, I'll buy the place subject to at a higher price, if ole Boyd gets to closing on time as agreed under the option, well, I lose the premium I paid and I'll need to sell it to him at that price....but, if he fails to the second (be'n the good ole boy he is) then I just keep the place and he'll need that stool.Fausto, not so close to Wayne, he'll get splattered, little more back towards you....that's good, right there, KA DING thanks.Speak'n of ole Wayne, he's on to someth'n there, a good Option Contract IS a purchase contract, in fact, you can go by a purchase contract and just take out all that default malarkey that nails the buyer if'n they don't buy the place.

Have you nailed down a date/time/location yet?

You really need to nail this down.