Usually taken for a website design or mobile app 400 Euro, but faced a problem: the customer pulls the rubber, gives long feedback, that constantly changes.
Yes, complete nonsense!
Who are You to put the client terms?!
I would have immediately sent you with this approach!
1. Show Your work
2. Show those who have paid You so much
3. this is not a problem and for 400 euros - the customer has the right to think!
If done correctly - you can maintain 2 projects in parallel and charge the client only for the actual time spent, not necessarily providing the screenshots of Your working process (via the software https://www.chronolapse.com/
, for example).
And how much time he will give the feedback - it is his problem.
A simple comparison: You stand on one side of the forest. Your income is the time it will take you the shortest way through the woods on his other side in a straight line.
The expectation is You met a tree on the way You approached the tree and stand still in front of him until then, until a person tells You he wants to see next.
The work (income) - You go through the forest in a straight line, until, until it encounters another tree on the way.
After waiting, You go around the tree and move on = doing the work.
It now remains to choose the number of options for addressing tree:
1st option - to wait any longer to get the tree and then go further (1 client per unit of time)
2nd option is to have an additional 1 or more ways to bypass wood in stock (2 or more clients per unit of time)
It is better to choose the 2nd option and 2-3 clients depending on the load intensity.