I just feel like these are the bulky regular transactions that can quickly add up if you're over charged a few $100 here or there.Thank you for your thoughts!

.- Your contractor may have over charged.- Your repairs may have included things that were not covered.Likely it is a combination of 2 or more of the above.  

CPA overcharges for bookkeeping services since that's not what they should be doing.

So many contractors have moved to "systems" that involve inside work because the can overcharge for them, yet not solve the water ingress. 

Second, you want to watch that valuation clause to make sure the insurance company isn't overcharging you by insuring your property at too high a value. 

For the first couple you may have to offer services very cheaply or even free because as you mentioned most good contractors are too busy being good contractors to do much else.Much of the time it is contractors sitting on their hands all day and overcharging that are actively looking at marketing.

But be careful of over charging - it will affect vacancies.

You will need to learn how much things cost so you can determine if you are being over charged for material and labor.  

Also, ask yourself whether pursuing this is worth it - for instance, does the amount that they overcharged you exceed the cost of legal expenses?

Your lender is overcharging you, both in fees and interest rate.