You call a car dealer and describe the car, “I need a 4-wheeler, with a steering wheel to change direction, a brake to stop, a accelerator to increase speed, 5 seats and a air conditioner. How much does the car cost you?” Guaranteed the consultant will be dumbfounded because he doesn't know what to say. If he meets a smart guy, he will report "Yes, only 350 million."

When you receive the car is a Kia Morning. You fall back because in your head is a Mercedes S600. You ask the car salesman, why is it so short, why is it so small, why is it so ugly, there will be 1000 why. Because you only have 10 minutes to describe the car, and only describe the function, not the detailed operating parameters. It is clear that the Kia Morning has all the functions you ask for.

But it's not the car you need, so you run it a few times and leave the car covered in dust.

So to get the correct quote of the software meet your expectation, you must be a person who carefully prepares the software requirements. Otherwise, you have some better mapping reference software, like I want to buy a car "like a BMW 750".