Just be careful hiring someone who is not licensed, insured, or paid under the table. There are many ways for an inexperienced cleaner to do a great deal of damage to your home. Some cleaning products will ruin marble, granite, carpet, etc.. If that cleaner is uninsured or paid under the table, you may not have much of a recourse in recovering your damages. In addition, you essentially become their employer if they are unlicensed, and you will be responsible for paying certain taxes, insurances, etc.. If they hurt themselves on your property they may sue you, especially if they are using your chemicals. There are plenty of horror stories out there.
The $200 for 5 hours is ball park for professional companies, because of costs involved in running a legitimate business. Will something bad definitely happen if you pay someone off the street and under the table? No, not definitely, just be informed with your decision to hire a cleaner.
There will always be trunk slammers and low ballers around, but you often get what you pay for, either in quality, risk, dependability, or all of the above.
There are a few legitimate cleaning companies that come on this board. Go with one of us who is doing the right thing.