chore(billing): Add more content to spend notifications (#11026)

* chore(billing): Add more content to spend notifications

* fix

* Update docs/product/alerts/notifications/index.mdx

Co-authored-by: Liza Mock <liza.mock@sentry.io>

* Update docs/product/alerts/notifications/index.mdx

Co-authored-by: Liza Mock <liza.mock@sentry.io>

* Update docs/product/alerts/notifications/index.mdx

Co-authored-by: Liza Mock <liza.mock@sentry.io>

* update with feedback

---------

Co-authored-by: Liza Mock <liza.mock@sentry.io>

docs/product/alerts/notifications/index.mdx

@@ -8,7 +8,7 @@ Sentry sends you notifications regarding workflow activities, [release deploys](
 
 - [Workflow](#workflow-notifications): Activity involving user actions and state changes on issues. This includes activities such as issue resolution, assignment, comments, and regressions.
 - [Deploy](#deploy-notifications): When a release you have commits on is deployed.
-- [Spend](#spend-notifications): When you're getting close to spending your reserved volume, your quotas are depleted, and/or your on-demand budget is being put to use.
+- [Spend](#spend-notifications): When you're getting close to spending your reserved volume, your quotas are depleted, and/or your pay-as-you-go budget is being put to use.
 - [Weekly Reports](#weekly-reports): A summary of your organization's Sentry activity.
 
 You can manage these notifications in **User Settings > Notifications**.
@@ -49,13 +49,33 @@ Sentry sends deploy notifications to users who have committed to the release tha
 
 ## Spend Notifications
 
-By default, Sentry sends spend notifications to all owners of an organization when:
+By default, Sentry sends spend notifications to all owners and billing members of an organization when:
 
-- 80% of the organization's reserved volume (for errors, transactions, and/or attachments) has been depleted.
-- The entire reserved volume and any on-demand budget for a category (such as errors, transactions, and/or attachments) has been depleted.
-- 80% of the organization's on-demand budget has been used.
+- 80% of the organization's reserved volume (such as errors, spans, and/or attachments) has been depleted.
+- The entire reserved volume and any pay-as-you-go budget for a category (such as errors, spans, and/or attachments) has been depleted.
+- 80% of the organization's pay-as-you-go budget has been used.
 
-Learn more in the [full Quotas documentation](/pricing/quotas/).
+Learn more in the [Pricing & Billing docs](/pricing/quotas/).
+
+### Spend Notifications for Your Organization
+
+Billing or owner members can set up their notification thresholds by going to: **Settings > Subscriptions > Notifications**.
+
+![Notifications tab of Subscription settings page](./img/subscription_notifications_settings.png)
+
+From here, you can customize the notification thresholds for your organization for when you're close to reaching one or both of the below:
+
+- **Subscription Consumption**: Set the percentage of the quota usage threshold(s) that will trigger a notification.
+
+- **Pay-as-you-go Consumption**: Set the percentage of the Pay-as-you-go usage threshold(s) that will trigger a notification.
+
+### Personal Spend Notifications
+
+Owner and billing members of an organization can also customize how they personally receive spend notifications. This can be done from the user's notification settings page:
+
+1. Go to the [**Notifications**](https://sentry.io/settings/account/notifications/) page (in your **User Settings**).
+2. Scroll to the **Spend** row and click on the cog wheel.
+3. From the [**Spend Notifications**](https://sentry.io/settings/account/notifications/quota/) page, you'll be able to select the types of notifications you get as well as how you'd like to get them (via Slack, email, and so on).
 
 ## Weekly Reports