Can anyone recommend a structural engineer/contractor that won't charge an arm and a leg to analyze?

The entry point is much lower, and I'll take the returns here all day long and not have to get into the Columbus arms race.

An escalation clause states that the buyer will increase the offer price to exceed a bonafide, arms length competitive offer by $X,XXX to a maximum offer price of $XXX,XXX. 

No ARMs via the Conventional 97.I've also been doing some reading about the “piggyback loan” program, which is typically reserved for buyers with above-average credit scores. 

My current brokerage does not offer a lending arm and I was wondering if it would be possible to be sponsored under my current broker as sales agent while sponsored under another broker as a lending agent.

Both FHA and conventional will make you pay PMI; I have a lender who does 5% down no PMI, but that is a 5 year ARM, so you probably want to refi at some point.

Home owners had ARMs back then and now they have 30yr 2.5-3% FRMs.

The SFR we would want to make our primary residence as soon as the current tenants are out, but because the duplex is tied to the house,  my current lender told me it would probably be a 20% down commercial 5 year ARM loan and hasn't been helpful since. 

Make sure it explicitly explains the process for termination if you are unhappy with their services, but especially if they violate the terms of your agreement.3.

Unless the seller tells me explicitly that they have to be cashed out immediately, I make them 3 offers.