You could use the time value of money formula to convert between one-time prices and subscriptions. just multiply annual price by 30 to get forever price.

So my $6 per month VPS would be about $2,000 upfront.

And a $500 game console would be a $1.50 monthly subscription. (Obviously glossing over tons of differences in say, a PS2 and a Stadia subscription)

It feels easier to ask customers for $1 per month than $360 up front... Especially since I don't know if my service will be up forever