yes you can orally extend an escrow. The party that relies on the oral extension is taking a huge risk, in this case a sale to another person, and should have extended in writing. The statute of frauds usually requires a writing in real estate matters but several exceptions to this rule exist. If you actually agreed (you said you have) then why did you sell to someone else? I agree your agent/broker never should have allowed it. You should consult with a local real estate attorney soon for advice and to get an idea of your actual liability.

yes you can sell and be IRS compliant. the general Idea with the IRS is to accurately report and classify your income and expenses. I would consult with an experienced CPA for advice on the correct reporting of a transaction such as this.

A trust provides some benefits such as retention of control of your estate and  flexibility regarding disposition of your estate.

If you have closed escrow on the purchase why did you sign the escrow paperwork that shows 2.5 % to the agent? By the way it should be paid ONLY to a licensed real estate BROKER not a salesperson. read your paperwork and check for this commission language (it is what escrow would need to write a commission instruction to the agent). If you are unsure of why the agent got paid consult with a local real estate attorney if you are upset with the agent making 2.5 percent for "what?15 mins" of time I would not go much further with this.