Free and Pro find the same problems with the same evidence. Pro gives you more of it: more personas at once, evidence kept longer, a bigger team. Prices are in US dollars; tax is added where it applies.
Saram bills the steps your personas take, weighted by how long each one takes: a step is 0.5 Usage plus 0.1 Usage for every second it runs, counted up to 30 seconds. A typical step is about 1 Usage, so about 2¢ on Free and 1.6¢ on Pro.
For scale: five personas walking through a sample shop's checkout used about 132 Usage, $2.65 on Free. Judging the results and replaying a problem to reproduce it are not charged.
Your model, your provider's bill
When personas think with a model you connect, through your own API key or subscription, your provider bills those model calls to you directly. They never come out of your Saram balance, and Saram's price does not include them.
How paying works
Prepaid. Runs spend from a balance: the month's included Usage first, then credit you bought.
Included Usage arrives each month with your plan and expires at the end of the month.
Top-ups are whole dollars from $10 to $500, and never expire. Automatic top-up refills your balance when it runs low, within a monthly budget you set.
No surprise overage. A run your balance cannot cover is refused before it starts, and nothing is charged. What a run holds and does not use goes back when it finishes.
Pro is $20 when you upgrade, then $20 on the 1st of every month. Cancel any time; Pro runs to the end of the month you paid for, then you are on Free.