What is free and what is Pro
The free tier is permanent. Pro removes the scan limit and adds the Market tab and the tools built on your history.
Free, permanently: twenty-five scans per account, any card added by search without limit, every price with its source and date, unlimited viewing of everything you own, set completion, the binder, the showcase, the trade list, the watchlist, weekly local backups, sync to your account and CSV export.
Zukan Pro: unlimited scans, Binder mode and buying mode, the Market tab, the value graph over time with profit and loss against what you paid, full price history, price alerts on watched cards and the dated, sourced collection report.
Pro is €39.99 a year with a three-day free trial, or €5.99 a month. There is no weekly plan. The line-by-line comparison is on the pricing page.