Is it possible to calculate the cost of the system without TK?

Question

Preparation of terms of reference

The customer wants to get the cost of the system without technical specifications, the scale of the system is unknown, the maximum that can be assumed is that the functionality of the desired system fully covers the functionality of Frontpad.ru , plus a few additions (according to my estimate, about 20-30 dynamic pages).
Features of the customer: ideas come one after another every time a meeting takes place, he fails to structurally state the main idea.
He agreed to the proposal to draw up a TOR, but refuses to pay for its development in principle (2-3 weeks of work). He says that either we make technical specifications, determine the cost, and he looks and decides whether he needs it, or the designer will draw layouts (you can pay for them - you can see them), and determine the cost from them.
Question: is it possible to give a more or less adequate estimate of the total cost of development under such conditions? And if so, how?

Answer 1

In a similar situation known to me, the customer, having ordered a cost estimate from a dozen different contractors, received a spread in the cost of the project from 400 thousand to 32 million rubles. (The customer eventually abandoned the project altogether).
I don’t know if there is any single correct solution in such a situation, but project cost estimation methods, the same PERT, can help you. In a nutshell:
Decompose tasks as much as necessary in order to evaluate them at least preliminary.
Perform, based on existing experience, an assessment of the timing of the resulting tasks on three points: optimistic, most likely, pessimistic. In these assessments, try to take into account possible risks.
Calculate the expected project time based on the resulting estimates, add a couple of standard deviations plus and minus: get a fairly wide range of total project time, but with a high probability including the time that may actually turn out.
Multiply the resulting estimates by the cost of your team's work (per hour / day - which unit was used in estimating the terms), thus getting an estimate of the cost of the project from above and below. Present the resulting fork and the scope of the project that formed its basis to the customer. Narrow the fork at your own risk.
If there is no experience on the basis of which it would be possible to estimate the scale of work, it is better to abandon the project.
If you are not ready to perform such an assessment for free, it is better to refuse the project.
If the scope of the project cannot be outlined even in such an approximate framework, it is better to abandon the project.
Avoid entering into a contract with a fixed, non-negotiable price based on such a superficial estimate.
High uncertainty at the initial stages of the project is a normal phenomenon, but taking on any obligations in such conditions is your risk. Assess if you are ready to go for it.

Answer 2

It is forbidden.

Answer 3

Turn to a fortuneteller, perhaps. But I do not think that this solution will suit the customer.

Answer 4

With a crystal ball.

Answer 5

what prevents to calculate the cost of Frontpad.ru and add %% ?
+ the corridor
is no offense, but if you needed this order, you would have already passed the first stage and would have bargained for the cost of completions and unaccounted
for in technologically advanced elements there are no questions at all about the calculation - to take and do
this is not Elon Musk's Rocket Science - flight in the middle of 2020 of a 100-seat rocket, when a single-seat one has not yet flown - try to calculate

Answer 6

Run away from him soon...
And if it's not joking, if you, TS, don't know how to use search, you'll have to walk and walk to TK...
Is there a service where an ordinary customer can create an approximate idea of ​​what a website should be like need to be developed?
Could you share a good technical task for the development of a website/web application?
Where can I find a standard TOR for the design and development of a mobile application?
Where can I find a standard TOR for the design and development of a mobile application?
What questions should be in the design brief?
How to draw up a technical task?
The contractor does not need TK. This is fine?
https://vk.com/doc399047259_464509206