When sending marketing messages we connect the system to your email provider.  Therefore the limits vary depending on your provider.

If you connect it to a regular provider such as your gmail account, you might only be able to send a few hundred emails per day.

But if connected to a professional level service such as Mailgun, Amazon SES, SendGrid etc. you can send tens of thousands of emails per day - assuming you have that many members of course!

Standard transaction emails such as membership confirmations and reminders are sent through our own email system.  Only marketing campaign emails need to be connected to your email provider.

Yes.  You can use any number of MailChimp sign-up forms to send leads you collect directly to the MailChimp service.  Additionally, you can also add new members who opt-in while they're signing up for your service.

We provide various levels of integration with a number of email providers depending on the type of integration you need.

We provide a built-in email campaign manager that you can populate with leads you collect from landing pages.

You can also connect your landing pages directly with many other email services.

However, for membership signups, we only send those email addresses directly to MailChimp.  But you can use a Zapier connection to send them to any other marketing service provider.