At what price points does it make sense to pay a Section 1031 intermediary to do a S1031???? 

There is a "parking arrangement" where an Exchange Accommodation Titleholder (part of the Qualified Intermediary operation) will acquire and hold or "park" legal title to either the replacement property or relinquished property, and there is a concurrent/simultaneous 1031 Exchange. 

If the unrepresented buyer comes in with the best offer my listing agent becomes an intermediary.

@Blake Harris if you are doing a 1031 exchange then by definition the previous property that the LLC held would no longer be owned by the LLC.In a traditional 1031 you sell a property and then buy a new one with the proceeds (that you never touch and were held by a qualified intermediary- be sure to do your HW before executing).

I think you should check with the protocols with a 1031X Intermediary before proceeding with this plan. 

Does anyone have a referral for a 1031 intermediary service?

When you sell an investment property and do a 1031 Exchange, the equity from that sale goes to a 3rd party Qualified Intermediary where it is held until it is used for the purchase of the replacement property.

Just a reminder that you need to work with a 1031 intermediary to properly do the transaction.

I understand Hubzu is a intermediary service and they don't care, I don't really expect them to.

People that own NNN now as well as 1031 intermediaries are really going to be out of luck.