Passes carry a visit count, an expiry date, and a list of which doors they open. Staff scan with a phone. No hardware, no spreadsheet.

Problem
Once access is limited to a number of visits, a date, or certain doors, someone has to check it every time. The tools for that are either a paper card or something built for a stadium.

Pain one
A pass sold to one person is easy to hand around, and at the desk there is nothing to check it against. The limit you sold and the limit you get are different numbers.
Features
Set the limits once. Every scan checks them.
Sell a package of ten entries. The count comes down at the door, and a scan that already happened is never counted twice.
A pass valid for thirty days. It expires on its own, so you do not chase anyone down.
A pass that opens the gym and the pool but not the sauna. Set it once per gate, and every scan checks it.
Use cases
Different venues, one pattern - access you hand out that runs out.
A gym and pool open to locals from November to March, sold at the front desk across three shifts.
A ten-entry card at the gate, for a business that operates twelve weeks a year.
The ten-swim card, off cardboard and onto a phone.
Showers, laundry and the pool block on one pass, scanned by seasonal staff.
A pass that covers the pool but not the sauna.
Ten-visit cards that run for the school holidays.
Twenty people, one service door, weekdays only, for six weeks.
A book of ten range buckets or karting sessions, counted down the same way.
This works where someone is already at the door with a phone. If the entrance is unattended and needs an electric lock to open, this is not the tool.
Scenario
A hotel builds a Winter Pass in Wardentry: ten visits, valid through March, pool and sauna open 2-6pm on Tuesdays and Thursdays, gym available anytime.
The system generates unique QR codes. The owner sends them by email, ready to share.
A member arrives. Staff scans the code with a phone. The door opens.
After ten visits or the expiry date, the pass stops working. No manual counting.
Set the count, the expiry and the doors. Staff scan with a phone, and the pass stops working when it runs out. No hardware to install.