Germany 242A ????????

Guys I am in Germany now and finding alot of really nice stuff in here,,and I would like to know if this is what I think it is??
Is this the 242a ?? If it is the book says its worth a ton more used,or cancelled correct?? This stamp looks gem to me?? Why is that the value is higher on stamps if they are used or cancelled sometimes?
A little confused here and need a brain hahhaa,,so I come here to the best!
Thanks so much for any input here

Also looking at a nice 246 A35 20th m on a 200m and there are 2 prices for this stamp..the highest price is fro INVERTED SURCHARGE..whats that mean? Inverted Surcharge..my stamp has the black 20 over the 200 is that what that means?

Inverted surcharge is upside down in relation to the stamp design.

Inflation-era Germany is hard to find genuinely used, so that is why the values are much higher. The mint stamps are generally plentiful.

On stamps where the used value is at a premium, you have to watch out for fake cancels, or cancels outside the normal period of the stamp's usage. For example, a 1970's cancel on a 1920's stamp doesn't count as used for purposes of catalogue value.

Thank you Cjd!

Just to add to the excellent advise already provided by CJD, because these stamps have been so plentiful in mint condition, there have been several major counterfeit cancel schemes in play since about the 1960s.

I have one of these that is cancelled. One of these days I will get it expertised (when I find it again).