Can I deactivate the TYPO3-Cache only for the AMP view?

Yes, you can deactivate the TYPO3-Cache for the AMP view by using this TypoScript:

[globalVar = GP:type = 1486816934]
  config.no_cache = 1
  page.config.no_cache = 1
[global]

Yes, you can disable the AMP view by using this TypoScript:

lib.amp.url.wrap = <!--link rel="amphtml" href="{$themes.configuration.baseurl}|"-->

Simply by using using this TypoScript-Constant:

themes.configuration.urlScheme = https

Info:

If you are using the AMP-Form, HTTPS/SSL is absolutely required!

You are able to translate or modify the localization labels simply by TypoScript:

plugin.tx_amp {
  _LOCAL_LANG {
    default {
      tx_amp_label.display_web_version = Web-Version anzeigen
    }
    de {
      tx_amp_label.display_web_version = Web-Version anzeigen
    }
    en {
      tx_amp_label.display_web_version = Display Web-Version
    }
  }
}

First of all, you need to enable the font Library. You also have to insert the HTML-Tag for including a Font into the headerDataTypoScript node. Just insert this TypoScript into your Extension-Template on your Detail-Page.

plugin.tx_amp {
  settings {
    amp {
      libraries {
        font = 1
      }
      # Add some header data
      headerData (
        <link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto+Condensed:300,400">
      )
    }
  }
}

Attention:

Not every CDN (Content delivery network) is allowed to include Web-Fonts on AMP-Pages. For more information visit: www.ampproject.org/docs/guides/responsive/custom_fonts

If you get the following error:

Response must contain the AMP-Access-Control-Allow-Source-Origin header
Form submission failed: Error: Response must contain the AMP-Access-Control-Allow-Source-Origin header _reported_

make sure you've set a complete baseurl like this:

plugin.tx_amp.settings.baseurl = https://www.typo3-openimmo.de/

Just comment out the AMP-Linkwrap:

lib.amp.url.wrap = <!--link rel="amphtml" href="{$themes.configuration.baseurl}|"-->