Hi! I run the Agile and DevOps product marketing team at Atlassian and one main part of a head of marketing's job is to manage budgets. Headed into the new fiscal year, I refined the process with my team so there are no more one-off Slacks.
Here is how I will be managing my budget process going forward:
1. I have a Confluence page with an embedded Jira Work Management form that links to my "to-do" list board. When a PMM wants to request budget, they head to the budget Confluence page:

2. Below is the embedded JWM form in Confluence:

3. After PMMs submit their requests, they can see their request, and the rest of the budget requests on the Confluence page with an embedded Jira Work Management board:

4. Our program manager set up Atlassian Automation on my board so I can review budget requests from 1 epic named "Budget Review". So now when a PMM fills out the budget form, it creates a new ticket on my Jira board, assigns it to me, and links to the "Budget review" epic via Automation.

5. Then I can see all budgets in 1 ticket to review vs clicking in to separate tickets:

6. I also set up the Jira slack integration so all new budget requests alert me in slack in my own private room (or any comments on tickets):

Hope that helps!