Its sounds simple, but the best way I find to approach someone is just to do it confidently - be direct and say something like "Hey how are you my name is Corey, whats your name?

Bigger Pockets has a ton of calculators, make sure to look at some sales and analyze them to help guide you to what type of deal will cash flow, then when the right one comes along you will be more confident in pulling the trigger. 

If the agent is so confident about everything going well, then they can have their commission held back until you get the property in your full possession, fully vacant and in the proper condition you agreed on....... let her $$ be on the line until everything is finished up correctly....The dual agent gets paid no matter how bad it goes for you....they have zero skin in the game after the sale.

I have been looking for an IRR excel calculator but they all seem too complex and I'm not confident with them. 

Obviously, I don't know your deal so 12% pref might work if you confident you are hitting 20%IRR and you need a big pref as a carrot to attract equity.

@Bashar Azzu with the crash if there is any ,we do not know whether it is going to be the crash or correction and correction is good .But if there is a crash there are other that come with the crash too like cash crunch,liquidity and lack of confidence in the market so it is always a good time to buy as long as there is a good deal.

Tell the broker that you have lost confidence, want to be let out unconditionally, and that you cannot assist in the sale of your home with a "pitch hitter." 

The Department of Defense prohibits it (SCRA for service members).You would typically see "Borrower must be in imminent danger of default or no less than 90 days past due" in a short sale package in 2014, maybe even up to 2016 but i'm confident no lender/servicer still in business would be stupid enough to try to get away with that today.A servicer CAN say, "Wait, you are current, you have income, you have assets, no, we aren't going to approve your request to consider a short sale" but their denial would be based on a lack of any imminent danger of default after a full short sale package was submitted and reviewed, not on, "borrower is not delinquent" and they would never say (now) "Borrower must be behind in payments for consideration". for military though, even if they are current, have income, have assets and are not in danger, the mere presentation of PCS orders (relocation) requires the servicer to consider (approve) a short sale request).

I feel confident about the rehab budget which includes a $10,000 contingency.

I don't really feel comfortable/confident in finding deals off market so will stick with browsing the MLS.