What many have asked for, testing in my VMs, Do Your Data Recovery 7.6 Pro works portably -- activation data is stored in the app's folder -- with no files besides the Start Menu & Desktop shortcuts added elsewhere. As a bonus, it also runs from the command line booting to a generic WinPE USB stick or ISO created with the Win10 ADK. That allows pulling the plug on a PC, then booting to a USB stick to run recovery without worrying about a running copy of Windows overwriting lost files, which lets you skip plugging the hard disk in elsewhere, or doing something like booting to a backup app USB stick, then backing up the hard disk [including free space], and using that image for file recovery.
Installation does add a couple of registry keys, one for the app & one for uninstall. And while it still installs to Program Files (x86)\, 32-bit and 64-bit versions are different.
As for how well it works, can't honestly say... It's been at least a few years since I had a hard disk problem that lost every file, and when I ran maybe a dozen recovery apps, I found mileage really does vary, with a few apps picking up a few files that none of the others would find & recover. Any of them would probably pick up a file that was accidentally deleted, as long as you caught it almost immediately, but when things are really screwed up you might have to try several. Which is why I collect these tools.