Do you hold a valid ECRA/ESA License?
An ECRA/ESA license is required by all electrical contractors in Ontario today in order to ensure both your safety as well as quality workmanship inspected by ESA. If they do not have this license, you may want to move to the next contractor on your list.
Are you a fully insured company?
It's important to know that the company doing the work for you, is fully insured. Not all contractors/electricians take out insurance as it's costly or they're not able to obtain it because of prior claims or infractions of one kind or another. However, it is important for a contractor that you hire to have. Your homeowners insurance may not cover problems should they occur and you will be left holding the responsibility if your contractor isn't insured and leaves. It's a costly and long battle to sue a company that goes out of business after a potentially expensive "error")
Will you take out all necessary permits and arrange for and necessary electrical audits/inspections?
While not all electrical work requires a permit or an audit or inspection upon completion of work, you need to know that your contractor will be responsible for obtaining the necessary permits and inspections/audits when they are needed. You certainly don't want a fly-by-night job done, only to have something come back on you in the long-run.)
Will you give me a written estimate?
Of course, some people will be happy with a contractor's word on cost, it's always best to have it on paper. If the contractor will only spew out a number and refuses to give you that figure and its possible breakdowns on paper for you to have and think about, it makes it a bit dubious as to what you are really in for. While that estimate may change during the work phase due to unforseen situations or safety issues already existing or for add-ins that you may want added in as the work progresses, the contractor will notify you of any changes at that point in time and wait for your approval before going ahead with the work. No contractor can 100% guarantee you that they will not find unforeseen issues and stick strictly to the estimate, he/she must be able to give you a starting point estimate to consider or even compare other contractors with and to.