Constructive, respectful, clearly articulated conversation should always be acceptable. Communication and growing pains are common and frankly should be anticipated. However, if a rational, calm, understanding demeanor can’t be achieved then I’d encourage other alternatives. 1. commission an expert to delegate/mediate. 2. choose a low hostility venue and moment {aloting sufficient time obviously} 3. Contact the office or proprietor directly. Sometimes, the administration is occupied and unaware of issues etc. Lastly, often the person off-site contacted is completely different, motivated to remedy {sales, money anticipated} and cool temper due to lower stress level.
The first step in the process is to inform the contractor of your issues and allow him a fair amount of time (generally 10 days is fair for most) to correct the discrepancies. If he fails to remedy your complaint in a reasonable amount of time (which varies from state to state) or just ignores you, you have the option to file a claim to their Bonding Company. Your state’s Department of Licenses will have their bonding information available. Call the bonding company and inform them of your issues. They will have a series of questions and documentation requirements in validating your claim.
Good Luck
What would I look under for there bonding company to file a complaint?
I agree with the Answer from Zoiya below however to answer your question you can find bonding, insurance and license information on the local contractor board web site. Each state has its own name for it. In Washington it is Labor and Industries, In Oregon it is The Oregon Construction Contractors Board or CCB for short. Hope that helps
First off why are you reporting it to the bond company? The reason is important because you may be trying to complain to the wrong person. Have you tried to resolve the issue with the contractor? Also you may report misconduct or poorly done work to the contractor license board in your state. A complaint to your board is the best place to start off if you cannot reach an agreement with the contractor. The surety bond would be contacted if the contractor failed to meet a financial obligation such as not paying a subcontractor, permit fees or suppliers etc. If you want to find the bond company for that reason look them up on the local board’s website and the surety company should be listed there
I also agree to zoiya respond and also rightturnconstruction best thing to do is to is to check on the contractors state web sight
this is the ca state entity that issue contractor license ,
In the State of Maryland any contractor that works on residential structures should have a Maryland Home Improvement Contractor’s (MHIC) License.
Hopefully you did due diligence before signing a contract with the tradesmen to verify they had an active license.
You can “go over their head” if they refuse to respond, or fail to keep their contractual agreement, and file a formal complaint with the Maryland Home Improvement Commission.
Here is the link describing your rights and the process to file a complaint. File a Complaint - Maryland Home Improvement Commission (MHIC) - Division of Occupational and Professional Licensing
The first step is always going to be to contact the contractor. The next step will be to contact the governing agency in your state. The Registrar of Contractors for example and file a formal complaint. After a job site inspection the agency will give the contractor a directive of what must be corrected or finished. If the contractor fails to abide by the directive, actions will be taken against the license and you can recover from the bond.
Your project should have likely required a permit.
Google your city’s building department website and look under the list of services that require a permit. If it doesn’t require a permit no there really isn’t much you can do besides the standard channels of reaching out to the company, going on to the BBB, etc…
If your city DOES require a permit then you will want to first do a permit search to see if they actually pulled one. If they didn’t then yes call the city immediately that’s a major issue and that contractor needs to deal with making it right for both you and the city!
If they did pull a permit then inquire to see the inspection results. If they didn’t have the project called in for inspection call the city and schedule an inspection date. The city inspector SHOULD be able to see any flaws that require being redone per IRC (International Residential Building Code) which (loophole) also requires deferring to the manufacturer’s best practices for those in the know 
This means that if there is indeed an issue, and you have a decent inspector then the city WILL INDEED HAVE YOUR BACK 
Also check your city’s county. Some cities don’t have their own building department but instead fall under a county building department. Once again good luck!