I was once an audiophile "novice" who had no clue what good sound meant, and made all the classic newbie mistakes. So, if you are new to high end audio, you'll need time to process the huge variety of loudspeakers available (new or used) at any price point you can imagine. You'll need time and patience to get yourself educated, not to mention a reasonable bank balance.
I began as a graduate student in the early 1980s with a pair of Mission speakers from the UK, because I foolishly believed in somebody's glowing review. It turned out to be a speaker that had a rising top end (many "audiophile" speakers do, so you need to be careful to see if you like that sort of "hot" sound). When I listened to my Missions over a period of a year or so with FM radio -- we are of course talking about 40 years ago, when there was no streaming, and FM radio was free and I lived in a university campus with an excellent FM radio station -- I found the speakers too bright sounding on a lot of material. As luck would have it, my PhD advisor decided to move midway through my degree to a new university, and I moved with him. I found a local audio dealer that was selling the Spendor SP1, another British speaker designed according to BBC standards, which meant incredibly good tonal accuracy, and very flat response. It was a revelation and I quickly traded my Missions for the Spendors, and never looked back..
The SP1 was so good that even today, I have in my house a later version, the SP1/2E, that is one of Robert Greene's, a well-known TAS reviewer, favorites. Within its dynamic limitations (8" cone woofer, with a separate midrange and tweeter), it's hard to think of another loudspeaker that can beat it within the design specs. That is, it is a dynamic cone loudspeaker that is small enough to be lifted easily (35 pounds or so), placed in a small room if necessary, and can be listened up close. There are audiophile giants, of course, but compared to the SP 1/2E, I find most horribly colored tonally. If you can't get the midrange right, all else is useless. I don't care how much bass a loudspeaker has or how loudly you can play it. Can you play a recording of a violin, a flute, a piano, or a soloist, and have it sound "natural", like in a concert hall. The SP1 family of loudspeakers passes that test, which most modern audiophile loudspeakers fail at still. There are more modern variants, like the Harbeth loudspeakers. I own also the Harbeth Monitor 40.1. It's much bulkier, and not as svelte as the SP1. Still, the Monitor 40.1 is less colored than the SP1.
My next major discovery was when I got my first job after graduation, and discovered at another local dealer in Hudson Valley, NY, the Quad ESL-63 electrostatic. That to me was a huge revelation to hear a loudspeaker that simply doesn't exist in the conventional sense of loudspeakers. Almost any loudspeaker has a coloration that gives it away. Even if you play it soft, you can hear it out and never confuse it with the real thing. The Quad 63 was the first loudspeaker that disappeared as a loudspeaker -- when you play a guitar or a piano, it creates the eerie sensation of the real thing that comes largely from the clever design that Peter Walker took 20 years to get right. I still own two versions of the Quad 63, the 2805 and the 2905. The original ESL 57 is not as clever a design, but it has a warmer sound that many find enticing.
My most recent acquisitions as a grizzled old audio veteran with a much larger budget -- working in AI in the San Francisco Bay Area does help with that! -- was my first horn loudspeakers -- the Klipsch La Scala -- and the largest electrostatic loudspeaker ever made, the Soundlab G9-7c that has 9 foot panels that are 3.5 feet wide. Now, we are getting into audiophile "silly money" territory, and both require a larger room, and care with the electronics driving them. I would not buy either of these as a novice, even if you had the money. You need to "work your way up the ladder", because you don't know yet what you like.
Think of it like trying to find the best restaurant to eat in. Should you eat at one of the fancy Michelin three-star restaurants in San Francisco? That would be silly, even if you could afford a $1000 dinner (not including the wine!). You might not like the food. It's best to start cheap, sample the inexpensive restaurants of different varieties -- French, Japanese, Indian, Italian etc. --- to see the kind of food you like to eat. You start to develop a bit of appreciation for food, and you can then work your way up the ladder in restaurants as well.
Good luck!