I used the commission I would have been entitled to to negotiate seller contribution towards closing costs (and thus avoided receiving income from the transaction as an added tax benefit).

She then stormed away and said she has to ask her broker about paying us the $500 out of her commission. 

If so, you will pay between $5K (flat rate) and $12K (6%) in commission.

THe seller NEEDED to sell at almost any cost... hours from crunch-time I was ready to walk, so the agents put in a little commission and I ponied up a few thousand.

I’ve offered a written contract to be recorded with the title company, proof that I will be commissioned as a Naval Officer in May, and proof of funds (just got pre-approved with a local lender).I really want to make this deal happen.

As commission is usually paid by Seller, there should be no reason to go it alone! 

The seller was an older gentleman selling off all his properties so he was happy about not having to pay 6% in agent’s commissions, being able to spread out the cap gains hit over 5 years, and getting the extra profit from collecting 5 years worth of interest payments without having to worry about toilets or tenants.

They want to make a commission by selling the property and moving on to the next.

It's worth noting that if your agent is successful, it's a huge opportunity cost for them to spend time on this because the commission is basically nothing.

Make sure your share of the commission is a fair share as well.