One of the benefits of people being able to just e-mail normally is that they don't have to be constantly logged into some weird website (which is probably just going to alert everybody's inboxes anyway.) The upside of not having to log in means we don't have to deal with heavy web traffic and associated costs as other project management services do, so we've passed that saving along to you.
Proj.email is also fairly easy to use, so we don't have high support staff costs either.
All payments are handled by PayPal who accept all major credit cards.
In your account area (ie https://yourcompany.proj.email) open the menu and navigate to Account > Settings. Click on Setup Payment. Select your country and enter a postcode (if applicable) and click on a credit card/paypal button and follow the payment flow. All billing and payment notifications are handled by PayPal.
At present we do not — instead we have a free trial for you to evaluate whether or not Proj.email is suitable for your team. Please make sure your free trial is used effectively before pulling the trigger on a subscription. If you need an additional week or two to evaluate, just ask.
We're required to charge additional GST/PST/HST and remit it to the Canadian government, and a USD exchange penalty + tax ontop of that would be significantly more than everyone else is paying.
If there's enough demand we will consider it. For the time being all of our hosting bills are in a defacto USD currency, so it's easier to budget if the bulk of our revenue is aligned with that.