You listed it on flippa already starting at a $1 bid with no reserve. Not sure why you would ask this now.
Also, its not a "4 letter" domain. "7" is not a letter.
I cannot really comment on the price from a vanity point of view, but the domain has zero presence online currently. So keep in mind you are pricing only for the vanity of the name.
Further expand on that and people who would be interested in a domain with the title CPA are people targeting marketers. These people usually have a brand name, and just register that.
I would say you might not get as much as you hoped from it.