There is something called decency. Taking advantage of people who clean your mess is just not decent.
It's only taking advantage if they have to do something that isn't agreed or fair. If he (or anyone) agrees to work for 5zl an hour, then it's their choice to do so. It wouldn't be fair to expect them to answer the phone, for instance.
Anyway, as I said, the rate is minimum 10 zl. in Warsaw.
Minimum? The only minimum is what the law says - which is about what, 5.5zl an hour after tax?
I don't even want to start with "you get what you pay for."
Not arguing with you there ;)
Anyway, in my experience, workers from the Indian sub-continent tend to have major emotional problems for some bizzare reason - they're very, very sensitive people and more trouble than they're worth.