Instead of a 'subscription', how about a rent-to-own payment model?
3 options:
- 1 time payment of $500 (guessing a 5 year development cycle)
- 5 yearly payments of $110 (total $550)
- 60 monthly payments of $10 (total $600)
That way if your budget allows a single purchase or yearly $110 payment you can do it.
But if you only work occasionally and need it for a couple of months a year, you can pay for the months you need to have export functionality. The software works so that you can build/test games, but won't export unless you are current with your payment. Once you've paid off the software it is permanently unlocked.
For many, $10 is much easier to come up with a month than $110 once a year.