Your engineer may have questions about how you want to use and classify data in Amplitude. Common questions follow, with resources to help you answer them.

## Could you provide a sample or example payload of the data issue you're seeing?

[User Lookup](/docs/analytics/user-data-lookup) lets you explore real-time data streams from actual users. You can also start with [Microscope](/docs/analytics/microscope) in a chart, then select **View User Streams** to drill down to User Lookup.

## What specific user or group properties do you need?

Refer to the [guide to events and properties by industry](/docs/get-started/select-events) for the most common selections. Start there first.

## How often do user properties need updating? Is updating on profile changes enough?

User properties reflect the state of the user. They [apply across all the user's future events](/docs/data/user-properties-and-events) until the next update. You don't have to send user properties with every event, because Amplitude fills in existing user property values for each event until the next update.

## Why is this classified as an event property rather than a user property?

The subject of the property value determines the property type. If a property describes a characteristic of a user, like location, language, device type, or referral source, it's a user property. If a property adds context to an event the user triggered, like the direction of a finger swipe or the title of a viewed article, it's an event property.

If your engineer asks this, look closely at the event to confirm you've classified it correctly.