Macro to distinguish sequential numbers and report a value to a different cell

I have some item numbers (stored as text) that when the item has different variations of it the item number is sequential, but if it is unique meaning that it does not have variations the number unique. Rather than manually going through each of these items and labeling in another column whether it is an item or grouped I figured a macro would fix the problem.

For example the item number typically is name-xxxxx-model, but the (xxxxx) can range from 3 to 5 numbers. So you would end up with something like the following:

1. name-xxx00-model item
2. name-xxx01-model grouped
3. name-xxx02-model grouped
4 name-xxx09-model item

OR

1. name-xx00-model item
2. name-xx01-model grouped
3. name-xx02-model grouped
4 name-xx09-model item


the items that are grouped may be more that just two. Additionally the numbers are being read as text.

Any assistance with this would be greatly appreciated