You don't use the apostrophe a lot in German (except for genitive-endings of x/s/z and proper names).
etwas is established, so no cigar. You are not wrong, though: sometimes the apostrophe is used to write down colloquial abbreviations like
'ne instead of
btryba wrote, I think the actual way it would be said in English is: "That's going to cost you (down the road)! "
I agree that your sentence sounds more natural in American English. One could also say, That will be costly. But saying, That will be costly sounds more formal.
I just saw that Foolmaster suggested,
"That will cost a lot!" or "That will be expensive!" I think either of these sentences also works.
I think, from the sound of it, that this is an idiom that is not being translated well. As an English Canadian it sounds as if it should translate as "That'll cost ya." If it is an indefinite price to pay, either in cash or kind, for an action that has just been performed. "That will cost you." Sounds like it should be proceeded by a number amount.
was is an colloquialism for
etwas, so it translates to
something and is part of the Prädikat
kosten. (The last part is IMHO. Knowing the grammar of ones mother tongue always is a bit more difficult.)
"Das wird kosten!" would translate to "That will cost!" and is a proper German sentence, although without context it's as useless as the former example :)
You can. But it changes the meaning. Caveat: I'm talking out of my Sprachgefühl here. An Austrian, Bavarian or [...] could understand these subtle differences differently.
irgendwas (colloquial for
irgend etwas) you now say that it will cost something at all. With
was (coll. for
etwas) it's meaning is rather that it might be costly.
Example would be you asking somebody for a price of something and the person answering
Das wird irgend[ et]was kosten. - it would mean that they don't know, they don't really care in this moment but that they are of the opinion that it will cost something for sure.
Another example: you helping a friend and telling him afterwards
Das wird [dich] irgend[ et]was kosten. would mean that you expect something in return sometimes. Using
Das wird [dich] [et]was kosten. in this situation would mean in contrast that it will be costly for him to recompensate you (used jokingly with friends asking for a lot of help).
kostet is third person singular.
kosten is first person plural, third person plural, as well as the infinitive.
In this sentence, it's the infinitive -- the conjugated verb is wird, third person singular of the helping verb werden which is used here to form the future.
Compare English where we say "That will cost..." and not "That will costs..." -- the verb "cost" is in the infinitive form when you use the helping verb "will".