You won’t be the only one building a subscription website on your platform of choice. To increase the chances of being unique, at least in the eyes of the visitors, you should go for a builder that has as many templates or customization features as possible. This will not only let you bring out the designer in you but also ensure that you present a unique and convincing design that inspires confidence. Your visitors will respect you more if your website doesn’t resemble two other subscription websites they visited a couple of days ago.
Google Sheets beat Microsoft to the punch and introduced a Checkbox as one of the Data Validation options. You can go to Insert > Checkbox to quickly create one, and you can customize it by going to Data > Data Validation. I've updated most of the Google Sheets versions of my checklists to use that feature. I hope Excel gets smart and introduces a similar feature some day.
A checklist is a type of job aid used to reduce failure by compensating for potential limits of human memory and attention. It helps to ensure consistency and completeness in carrying out a task. A basic example is the "to do list". A more advanced checklist would be a schedule, which lays out tasks to be done according to time of day or other factors. A primary task in checklist is documentation of the task and auditing against the documentation.