Hi ToddMcF2002,
I'm not sure what you mean by "in place upgrades". I think normally upgrading iOS, or upgrading the version of an app, should not delete saved data from the app. However, I've read some people have had problems like that. Also, something goes wrong during an update, restoring from an older backup will not preserve newer data.
Before upgrading, it is safest to first transfer purchases made on the device itself to a computer, and then back up the device onto the computer.
Transferring purchases onto a computer can be done through iTunes (on Windows, right-click the device and choose "transfer purchases"). This can be done even if several people with different accounts have made purchases on the device, but then you must "authorize" the computer for all of those accounts. See
this description on Apple's support pages.
Once you've transferred purchases onto a computer, you can back up the device (again right-click the device in iTunes and choose "back up"). This should store the saved games etc. so that if something goes wrong during the update you can restore them from the backup.
Apple does also have a cloud storage option called iCloud; as far as I know it should be possible to back up a device onto cloud storage. However, I have not used it myself and I have no idea if it is possible to use that option if the device contains apps from several accounts.
(If someone knows more about this please feel free to correct/add details.)