Landlord Compliance Deadlines

Landlords: how do you keep track of compliance deadlines? I'm researching how landlords across the UK manage property compliance and paperwork, and I'd really appreciate some honest feedback. Things like gas safety certificates, electrical safety reports, landlord registration, deposit protection and tenancy paperwork can all have different deadlines depending on where the property is located. I'm interested in how landlords actually manage this in practice: 1. How do you keep track of your deadlines? A calendar, spreadsheet, letting agent, dedicated software, or something else? 2. Have you ever nearly missed—or actually missed—a renewal or compliance deadline? What happened? 3. What is the most frustrating or confusing part of keeping your property compliant? 4. Have you tried any landlord compliance apps or trackers? What did they do well, and what was missing? 5. Would you pay a small one-off fee (£3–£10) for a tool that genuinely solved a problem your current system doesn't? If not, why not? I'm at the research stage and haven't built or got anything to sell. I'm trying to understand the real problems landlords face before deciding whether there's a useful solution worth creating. Thanks for sharing your experiences. Any honest feedback, including that existing free tools do the job perfectly well, is welcome.