Should we use "open tickets" in our type of business?

[tiltedWC]

Hello all! We have an axe throwing business and take deposits online for booking a lane or over the phone. I am trying to find the best way to check out our customers and if "open tickets" would be sufficient and easier than what we are doing now. Our customers, book online, pay a deposit, then check out when they are done and sometimes purchase merchandise when checking out. We would need to deduct their previously paid deposit from their total balance. Their coach also generally receives a tip. (we have about 8-10 different coaches on a busy night). 

Does anyone here use open tickets for this type of business? I need checkout to run smoother for everyone involved. Thanks for any input you have!