> list of vehicles showing the 49 vehicles that need mileage information.
> The mileage that gets submitted through the form updates the list (this would have to be monthly, and we cannot delete the past month)
Your current system with the form should work fine for this I think. I assume you have a table that has all 49 vehicles in it, with one record per vehicle? If so, link that table to the form (I think you've already done this)
After that, use conditional rollups and lookups on the created date of the form submission to display the data from the latest form submission. Here's a link to a base where this can be seen in action
Creation / explanation:
1. Have all the records linked to a single record called `Rollup`
2. In the `Rollup` table, create a rollup field on the `Created Date` value from `Table 1` with the formula `MAX(values)`
- This will give us the latest date
3. In `Table 1`, create a lookup field to pull over the most recent `Created Date` from the `Rollup` table
4. Use a formula field to check the `Created Date` value against the most recent date pulled in via step 3
> Flags the vehicles that need mileage information.
For this, you'd pull the form's submission date over to the table that holds all your vehicle data, and use a formula field to check whether that vehicle needed it's mileage information submitted, does that make sense? Without knowing the exact criteria you use for this I can't suggest anything I'm afraid