Sort:  

it depends on the coins volume, look at the market history and bids and you get an idea of what you can bet.
This particular coin has a good volume on bittrex so you can probably get away until 10 eth bets

Coin Marketplace

STEEM 0.12
TRX 0.22
JST 0.030
BTC 81960.88
ETH 1879.29
USDT 1.00
SBD 0.79