I would do as much research as possible on the companies and domain and be prepared to spend if you really want. I think there is 60 days after it expires while it is owned by the current registrar and so the last owner can renew. Then it drops to whomever has the fastest computer to snap it up. I usually recommend clients look for another domain unless it's perfect. (Please correct me if I am wrong or out of date.)

This is basically my experience over 10 years:

I turned down hundred dollar offers and bought the domain for $8 from a registrar.

I let a less ideal one expire without saying anything and bought it from a registrar.

I had multiple companies offering "exclusive" sale of the same domain (different prices). I put in offers and lost in auction.

I went to the domain owner and asked if they would sell it directly. They renewed for 5 years and refused to sell.

We bought an ideal domain for $1200 where the domain was available when we started and weeks later was registered by someone else. It seemed unlucky and a little suspicious.

I sold a domain for $375 once. The guy seemed nice but I was surprised when a corporate website went up soon after.

I tried to buy a domain and they said "20". I was excited until they said "$20,000".