I would like to clarify the submissions limit for the Starter Plan

So just so I'm clear, if I go with the starter option, I can only have 100 submissions???

Yes, that's correct. Free accounts are limited to just 100 submissions per month total. And the following:

-10 Payment Submissions. This limit is applied when you use our payment gateway in your form and accept payments. Example, Paypal. 

-100MB of File Storage space. Applies when you have a file upload field in your form.

-5 Forms. 

-500 Total Submissions Storage. The total number of submissions from all your forms that you can store on your account. If you surpass this limit, the system will automatically delete the older submissions to keep you on this limit. 

Let us know if you have further questions.