For processing payments, Salestrekker is using Stripe as service provider.

"Stripe is an Irish technology company operating in over 25 countries that allows both private individuals and businesses to accept payments over the internet. Stripe focuses on providing the technical, fraud prevention, and banking infrastructure required to operate on-line payment systems." (Quote source: Wikipedia)
To learn more, please visit: https://stripe.com/about

Stripe bills the account for the exact time you use the account. For example, if you had annual subscription for 10 users on our $39.99 plan you were invoiced:
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10 users x $39.99 x 12 months = $4,798.8 + GST = $5,278.68

At first subscription you have been billed accordingly.

Lets presume you have been using Salestrekker like this for 5 months and your subscription was running. Your account credited looks like this:

$4,798.8 - 10 users x $39.99 x 5 months = $4,798.8 - 1,999.5 = $2,979.3 left

Now you want to make certain changes. Want to change subscription to Mortgage Broker on monthly level and reduce number of users to 7, of which 3 are Mortgage Brokers and 4 are Loan processing staff. Your new billing will be:

3 Mortgage brokers x $129.99 + 4 Loan processors x $59.99 = $389.97 + $239.96
​Total monthly = $629.93 + GST = $692.92

So after inducing changes your new monthly Invoice (including taxes) is $629.92 but you won't be charged immediately, because you have $2,979.3 left on your credits from your previous billing. Salestrekker will keep running and won't charge your subscription until all credits are spent.

So in our example you will have credits to last you full 4 months and won't be billed in that period:
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$2,979.3 - 4 x $629.92 = $2,979.3 - $2,519.68 = $459.62

On the 5th month you will pay only $233.3 as you also have $459.62 credits left ($629.92 - $459.62).

After that each monthly invoice of $692.92 will be charged on next invoice date.
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