A few years ago cup and saucer sets were getting really good prices, for the quality made ones.When using eBay for an idea on what things sell for be aware that sellers can ask anything they want for an item--it doesn't mean someone will buy it at that price. Always search completed sales, not items currently for sale, to get an idea of what buyers are willing to pay.
The price being asked for the one in your eBay link is on the high side of what you'll find similar pieces for in a higher-end antique or collectables shop, which is considerably higher than what people will normally pay, and at that price I'd expect it to sit unsold for quite a long time unless someone who's looking for a replacement in the exact same pattern happens to find it, in which case they may indeed pay the asking price.
I've spent decades buying and selling at small, local auctions, as well as at the largest international auctions. Common modern tea sets such as the one in question can be found regularly at most local auctions where they regularly sell for a couple dollars up to as much as $10 on very good day.