I heard that fees for listing altcoin is too expensive even in small exchange site.
Take a look at this article here
The Cost to Get Listed on a Crypto ExchangeAccording to the article the listing fee is around $6,000-$30,000 for small exchange and $60,000-$300,000 for medium size exchange and for big exchanges the fees is too expensive.
I don't know if this is accurate but I believe that there are some exchanges with lesser fee.
It is the most lucrative business now in the cryptocurrency industry, no wonder there are so many exchanged based ICO right now, they are all vying for a slice in the market and IEO has become the new trend because investors want listing right away so they can trade their coin right away.