https://www.askmehelpdesk.com/attachment.php?attachmentid=38088&stc=1&d=1321468784
Front 5 steps crumbling badly (actually a little worse on the left than in the attached pic)on the house I'm buying, but not closing on the place until Nov 28th, and contractor won't guaranty their work after Nov 1st because of the season. Thinking about buying a set of 4 steps risers and setting the temporary set right over the top so I don't get sued and the mailman won't hate me. Please tell me why I'm wrong and what I should do instead. Thanks!

OR... do I essentially build it upside-down, so the (custom)risers only secure the boards(steps)so the whole thing can nest within the existing steps?

That is a fairly inexpensive way to get around bad steps. Affix the stingers to the sides of the existing steps with lead anchors or red heads and lay 5/4 boards across. Screw the boards to the stringers. Some people put construction adhesive on the stringers and deck boards. You may have to adjust the first step to keep the risers constant.