Loopnet is a good site to check the commercial players in those areas you are interested in....Then you can go to their iindividual sites, check out those agents that have the listings and contact them. 

These large players that use wholesalers with assignable contracts should be careful.

Who are the major players? 

Call the big players and see what they offer.

One of the Secrets to winning is to play pro ball with pro players.!

You may also (which is a good idea) attend the sale to get to know who the players are before you Invest (Learn as much as you can first before you Invest).

With deficiencies, no one is going to loan you on the property, so you'll have to plan on self-funding or funding outside traditional position players. 

My broker says he's very aggressive and says he does these all the time, but I know all the big players in this area and none of the landlords that I know are going to pay more than $30K -$35K 'cash' of their own money with that kind of risk (4 years that 'heirs' might come forward and claim rights to the property being the biggest).  

You also need motivated players, an owner is not so picky, but your first buyer may have buyer's remorse and shown a better deal they may be willing to get out of the contract.

I don't really care for the turn-key outfits as I think that having multiple players keeps checks and balances in play.