Buying Off Market after Realtor Located Question

[Lee Fahy]

Situation:

I have a realtor who I've worked with on several deals in the past and she text me an opportunity to buy a 16 unit apartment building. I do not have a buyers contract with her and she does not have any investor/investment experience or knowledge. The deal she described was out of my range and I decided to pass on the spot. 

Weeks go by and I decide to off-hand call the owner and leave a message to give me a call. He indicates an entirely difference price that he needs to be done with the building and this price is in my realm. I go see the building and he says he's dealing with a realtor but the relationship was coming to a close and the price he quoted me was without realtor commissions.

1) Being I do not have a buyers contract in place with the realtor who text me the information am I under any obligation to her in this deal?

2) As an apartment building and commercial deal how long after the seller's obligation is over to his realtor does he have to wait to sell the building to me?

The deal is a COD with mutually beneficial T's and C's but this only holds if the commissions are not involved. Any help would be greatly appreciated.