Yes, you can increase the number of API calls by sending an email to Alpaca Support ([email protected]).
Alpaca is willing to increase your rate limit to 1,000/calls a minute with the understanding that the account will be updated to a non-retail account. When your account is non-retail your orders are not routed to wholesale market makers; orders are routed to the market using institutional-level smart order routers. Alpaca is charged for these smart order routers and you will pay a fee of 40 mils ($0.004) per expected share. Your orders will interact with displayed and non-displayed venues with the National Market System.
Please note - your orders will be sent out as “not held orders” and will not be covered orders under Reg NMS. There are no additional charges to remove liquidity, 40 mils is the all-in cost for trade execution.