depends where you are from? are you really from Africa? no one replied because you gave very little information on your location. shipping from other countries to Africa will cost $30 alone. the more info you give, the more likely you will get helped.
There is a store here that sells $30 badminton shoes but they are crap. The reason why badminton shoes are expensive is because they work. I don't recommend paying any less than $55 for badminton shoes.
What do you expect from 30$ shoes? Please remind yourself that injuries caused by wrong / bad shoes would SUCK and may cause higher costs in the future... Do something for your feets and your healthy and get some solid shoes.