Found 2 биржи where Api3 is traded for ETH. According to the data on 28 May the most optimal price to exchange API3 for ETH is Ξ0 for 1 Api3. This rate is fixed at Bilaxy at the maximum trading volume of the pair API3/ETH - 12.5 ETH.
The maximum daily trading volume is observed in the API3/USDT trading pair at Huobi Global and reaches Ξ 589.23 (0% of the exchange's total trading volumes) at the price Ξ 0 per 1 API3.
The minimum price to buy API3 for ETH is 0 - on the exchange Bilaxy.