Hi I find that well designed and constructed speakers last a really long time. I have vintage Altec Lansings and Klipsch (not the corner ones though) and they have the original drivers and are just fine after nearly 50 years. Some other brands are less durable. It is not necessarily more cost is equal to better speakers. Cheap ones though excepted. Pretty much any below $200 each is not going to deliver the sound quality or durability you want. Clearance sales at some of the better quality audio stores can be a good source for speakers. I have seen some really nice speakers the list for over $500 each going for as little as $200.
I've gotten some good deals from clearance sales. I have a friend who run an audio store, and each time that they have new arrivals, I am one of the first persons that he calls. There are speakers that I've gotten for less than a thousand bucks that still sound pretty good after many years of using them. So, I support the idea of checking such stores out for some good deals.