Yes adjectives always come before the modified noun, and verbs come at the end of the sentence (as long as you're dealing with simple sentences that don't have subordinate clauses).
Let's remember these patterns:
- もっと大きい車が欲しいです。
I want a bigger car. (than the car I have / than the car I'm seeing)
- 大きい方が欲しいです。
I want the bigger one. (between the two cars I'm seeing now)
- 大きい方の車が欲しいです。
I want the bigger car. (between the two cars I'm seeing now)
So when you're comparing two cars, you can use either of the last two sentences. That's how 方 works — selecting one from two options.
However, when you are not comparing two things but want to say "a bigger one", "a cheaper one", etc., you should use もっと, which is an adverb that corresponds to "more".
Examples:
- もっと安い車を見せてください。 Please show me cheaper cars.
- もっと高く飛びたい。 I want to jump higher.
- もっとたくさん食べなさい。 Eat more.
Bonus (I hope the following additions won't confuse you):
- もっと can be used in combination of 方 and mean "even (more)".
この車の方がもっと大きい。 This car is even bigger.
- より can be used similarly to もっと in formal sentences.
より小さい車が見たかった。 I wanted to see smaller cars.