I was actually in the same boat you were in, exhasuted from sending out certified letters to OC, CRA, and Collection companies, that bill can rack up very quick, I did use a repair company and it worked, but I learned some lessons really quick, the first one was once you send in your report make sure that you keep track of the accounts that they are working on for you, another issue is they will attack every account on your report so make sure you communicate with them on which accounts you want them to deal with, and make sure they only deal with them.
If your interested in the company name send me a PM, If I remember correctly it was 80.00 for initial then 45.00 a month, once the accounts are situated like you want them, they will also want to extend out to make sure all "disputed" remarks are off your report (which, I did)..Dont let them have free reign, tell them what you want done...
