Good advice on here and I see both sides of what's being said and asked. As for the credit cards, you really don't want a $0 balance. Of course you want it as low as possible, but it should always remain LESS than 50% of the high reported (or limit).
As for these agencies you speak of... there are the kind that go after the credit agencies to remove accounts that are not yours, colelctions that have been paid, etc. Something that was 30 days late 5 years ago will not impact credit to the point of not qualifying. Something 30 days late within the past 1 year will impact greatly, 1 - 3 yrs and you're on the fence. These places you speak of, and I would personally only use bank recommended or bank affiliated ones, are helpful if a person does not have the time to make all the necessary calls and stay on top of both the reporting account and the agency.
Bottom line B, your friends can do it on their own... heck, I managed to go up almost 100 points in 6 months simply by staying on top of equifax, experian, and trans union, skipping customer service at credit agencies and woriking with collection department managers, working with my bank, not taking no for answers, and A LOT of support from Nicole.
The best way to fix credit...
Stop asking for it or having places hit it. The more inqueries, the lower the score goes. Because I didn't know better and was looking for a house since January, I had 12+ hits on my credit between Jan and May. That's not good at all. I'd be sitting much prettier if a) mortgage places knew how to pull it and b) I pulled it myself first.
Reduce your D::I. debt to income is crucial. This will not effect FICO scoring, but it will impact your ability to borrow. You can have a 700+ score, if your D::I is over 42%, good luck borrowing.
Reduce unsecure debt. Pay down credit cards on time starting with the highest interest rate cards and close all "store" cards... unless you really really need that best buy card
Always pay the minimum if you can't afford more. Sure, it's nice to pay over the minimum or else things would never be paid down. If you're financially tight though, at least figure a way to pay the minimum. Some places will not report 30 days late until it actually hits 30 days. Some will report 30 days late if you are 1 day late. If you are having difficulty paying, call the place. I learned the hard way. Pick up the phone before they call you. Talk to customer service, managers, collections, etc and ask if they can help. The worst they can say is no, but it never hurts to ask.
Consolidate
Pay on time
Have affordable secured debt that is paid on time (and does not kill your D::I).
That's it man. Yes, I know this is what you tell them, but as far as going to a company to fix it, why spend the money when you can do it yourself. Go to freecreditreport.com, get your report, look for things you feel shouldn't be on there, and get to work. Research research research. I sound like a friggin commercial, but seriously, if I did it on my own, it can't be that difficult.