Most DAZStudio stuff you will want to install to the content folder.  It should take care of that when you click on the installer.  On my computer the path to the content folder is as follows.  C:Program Files (x86)DAZStudiocontent.  Characters like V4 will install inside the runtime folder which is a sub folder of the content folder. When you click on the installer it usually asks if you want to install to DAZStudio or Poser.  Choose DAZStudio, then it will probably present you with a choice of installation paths.  You want to choose the path to the content folder.

 

Here is the first installer screen.

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