Is it worth it to work with such an artist?

Question

Work organization

We are offered several models of work:
1. You write your "Wishlist", we formalize them in those tasks. You pay in full the hours that you spent on tasks, hours for updating PHP on the server and other software, refactoring, optimization.
The time in the tasks may differ from the predicted one in any direction (no restrictions)
1000 rub \ h No deadline
2. Same as the first one, but PM is added.
1600r/h Gar. there is no time limit
3. You formalize tasks and algorithms on your side, you bear the risks of incorrect formulation of the problem.
4. Payment is fixed for the task, we take all the risks (As I understand it is 3 times more expensive)

Answer 1

It's worth it, and choose the second model, renting a Makarov pistol for 600 rubles per hour is not so expensive.

Answer 2

Nothing prevents you from looking for a team that will agree to a contract with a warranty period. If not with a warranty period, but with payment for the entire project, there are many who want it, but this, of course, does not exclude big problems regarding improvements. It is reasonable to introduce staged payment and break the implementation level into 3-4 stages, for example: prototype, product, product production version, testing.
If you are one of those customers whose product is not formalized, but they urgently (!), need a warranty period, and a lot of edits are expected from all levels of management, then everything is very correctly offered to you: either an hourly wage or 3 rubles. expensive. If you are not it or you have an art director, you need to charge +50% more)