Redownloading apps on new phone - storage issues

Bought a new Lumia 1520 recently and one of the first things I did was to redownload all my apps from Purchase history on windowsphone.com (more than 100 apps). Went through and clicked reinstall on them all. After that just to make sure that all of them actually got installed I went through the process again. However this time I was looking through my games and comparing them with what was being downloaded and it was downloading the same apps again which I had already downloaded and noticed that the games was taking up multiple space on the internal memory so started to cancel all the downloads after that and now I don't know if they all got downloaded. How can the same app/game chew up more space than it actually is? Is there any way to see accurately how much space each app is taking up now?

Check Storage check and you get fairly accurate usage for each app as well as the space it uses for app data.

Is that an app? In settings it just shows the total amount of games+app space. Would I have to do a factory reset to be able to use the whole 32GB of storage again or is there any way to get rid of the hided duplicates? I read somewhere a long time ago that a temporary file gets created until a download is complete, is this true? Is there any way to get rid of them in that case?

storage check | Windows Phone Apps+Games Store (India)

Install the app. Use it to clear temporary files. Partial app downloads do take up space, but storage check can remove them.