Any home that one considers to buy ought to have it's wiring checked for aluminum wiring prior to a signature on the documents. It can function fine if kept within it's limits. Lights and lighting are typically fine, but any circuit posed with a varying amp load ought to be replaced; however, if one circuit is being swapped out, it's better to bite the bullet and change everything and ignore the 'grandfathering' option.
We had a house that was all knob and tube next to live gas lines, the latter got disconnected and vented. A latter one has one continuous ground for all the circuits, making 'short circuit searches' a real bug chase....
Know ahead of what you want to upgrade....copper and alum wiring together in one installation is considered a real hazard...
"Know thyself....Then, know everything else in close proximity to you and ;oved ones....." ;)