I would venture to guess that you bringing an estimate from a contractor saying the work will cost less than $100k would have NO impact (at best) and a negative impact (more likely) because, back to the original point:  the discomfort may well be with you and your ability to excellently execute this complex deal. 

That would minimize their dishes until you are able to get the problem fixed.You already have finances going out for repairs, but I think it a good gesture at least offer them a hotel for a night or two prior to Monday while they wait, & the plates, etc are inexpensive and let them know you are concerned for their discomfort and are trying to make things easier for them.

If I were the parent my discomfort would come from the quick change of heart in your plans.

Thank you all for resting my discomfort, here.

I would opt for somethingHard to quantify in terms of pricePurely in the "gift zone"For example, if you give them a $50 gift card there is a very real human tendency to compare the dollar value to what you perceive the discomfort to have been worth, and most years, and ESPECIALLY this year, you don't want anyone's lizard brain doing that calculation.Something like a bottle of wine and a doggie-pampering gift basket accompanied by a note expressing something like "I am thankful for you and apologize for the inconvenience you experiences around this roofing fiasco. 

It can surely be overwhelming, and that discomfort will get more... comfortable? 

Cognitive dissonance  Cognitive dissonance is a state of mental discomfort from holding two competing beliefs.

Your job us to sell the next step on the phone.If you are part of the .01% of marketers who are willing to exoerience the discomfort of failing and persistently mailing then tweaking their campaign, then you know that you are merely testing what would and doesn't. 

Real estates fuel is driven by the 3D affect...death, divorce, and discomfort.

Pursue your dreams and deal with the discomfort of not having her support.