Define a data model - Best Practices

I am trying to figure out how my data model should be set up. Here is the run down.

Lets say I am building a car app. The user will come to a screen that is a list of cars grouped into sections based on make (Chevy, Ford, Etc.)

The user clicks add, and gets a modul screen to select a make of car then screen to select model and from there fill in a form with about 40 textFields.

I was thinking about saving each car in core data as a dictionary as the form is going to be slightly different for each model/make. Is there a better solution or is that a solid model?

Well what are those 40 fields going to be about, detailed specifics for each make/model?

So if I choose Ford Ranger, is the form standard for all other car selections, like Chevy Camaro? Iow, is that form going to ask the same thing regardless of make and mode; such as HP, cylinders, CC etc?

The model for a car should be standard I think. Its a pretty well defined object.

Yes the fields are specific for that model. But not quite what you think. Its more like camber, tow (front/rear), shock oil weight, motor tuning. More racing focused. But different makes will have different options so I cannot reuse the same form. I wish it were that easy.

Right now I am using a framework SwiftForms to help easily create the forms, when saving the details via the framework it creates a key:value dictionary. so my thought is that i create a “vehicle” entity and it has the attributes “make” (string), “model” (string), “details” (dictionary).