You don't need to have a POS system to use Slick. Slick can record checkout transactions if clients pay by cash or card on your existing card reader.
This means you can use Slick to client bills for services and retail products, assigning them correctly to stylists for commission calculations. You can apply discounts (percentage or absolute £ amount), record part cash payment, record payment by voucher, and record tips on card.
Slick offers free email receipts to clients which you can add your salon logo to and a link for clients to rebook next time.
Slick allows you to cash up at the end of the day, over over any date range, showing you total takings, by cash, card, and voucher. You can record petty cash and leave notes. You will also see a transaction log of every client checked out in that time period, with the ability to view every transaction receipt.