Alpaca and TradeStation differ on 13 of 21 points TradersPost compares: index options, futures, crypto, short selling and 9 more. Both support stocks, stock options, market orders, limit orders, stop limit orders, modify open orders and paper accounts.
Index Options
Not supported
Supported
Futures
Not supported
Supported
Crypto
Supported
Not supported
Short selling
Partial
All but Crypto
Supported
Fractional quantity
Partial
All but Stock Options
Not supported
Stop orders
Limited
Crypto: Stop-limit only. Plain stop orders are not offered.
Supported
Trailing stops
Partial
All but Crypto and Stock Options
Supported
Bracket orders
Partial
All but Crypto and Stock Options
Supported
Day orders
Partial
All but Crypto
Supported
Good till canceled orders
Partial
All but Stock Options
Supported
Immediate or cancel orders
Partial
All but Stock Options
Supported
Fill or kill orders
Partial
All but Crypto and Stock Options
Supported
Trailing stop attached to entry
Not supported
Partial
Stocks
Alpaca: short selling and day orders aren't available on crypto.
Alpaca: fractional quantity, good till canceled orders and immediate or cancel orders aren't available on stock options.
Alpaca: trailing stops, bracket orders and fill or kill orders aren't available on crypto and stock options.
Link to this comparison /compare/connections/alpaca-vs-tradestation
Brokers change their rules, so check their docs before you connect. TradersPost does not recommend a broker.