АТОЛ offers a standard online cash register for rent. Customers pay for goods through the online store, and after the transaction is confirmed in the aggregator, the information is sent to АТОЛ, which generates an electronic receipt and sends it to the OFD. Then the data is transmitted to the tax authorities, and the receipt is received by the customer. This is necessary to avoid a fine of 30,000 rubles for not having an online cash register according to the 54th law, or 10,000 rubles for not sending an electronic receipt. Before making a decision, check the integrations with payment systems that АТОЛ supports. I didn't bother with Yandex.Checkout, but if you have a different aggregator or a specific acquiring bank, as well as a rare CMS, there may be integration issues. If everything is standard, you don’t need to worry; everything will work smoothly. The service prices are quite high. Everyone decides for themselves whether to look for alternatives or to purchase an online cash register.