Yuugen Kaisha

Sexy, supernaturally powered women with a group of assistants battling various and sundry ghosts and spirits. sometimes against competition. There is a quantum jump in animation between this and GS Mikami. But PQC has a better musical score than GS Mikami does. Despite the fact they came out around the same time, and having seen Phantom Quest Corp. several years beore, I still like Ghost Sweeper Mikami a little bit more. But, if you happen to like attractive self-confident and powerful women going around 'ghost busting' (cough, cough) you will like both of these shows. 

Both revolve around attractive female lead(s) who work for/with police trying to keep their cities safe, Yuugen Kaisha(or "Phantom Quest Corp" as I first knew it) has a supernatural theme to it while You're Under Arrest is more "slice-of-life" like. Adventure, comedy, action and little romance can all be found in both series. Both from 1995/6 with decent graphics and added bonus: good dubs. Worth noting "Yuugen Kaisha" has only 4 episodes while "You're Under Arrest" complete TV series has 96+ episodes excluding the movie, OVAs and specials. I think if you liked one you will like the other. 

Nightwalker and Phantom Quest Corp are both supernatural theme anime from the 1990's. Both titles have a business that investigates the paranormal and the main character in both titles have a child sidekick. While Phantom Quest Corp is more comedic than Nightwalker, both titles have a nice blend of comedy and action. If you liked one, you'd like the other. 

Both produced by Madhouse, both involve eliminating supernatural forces, but DMC is more serious and dramatic while PQ is more comic. Ah, and both main characters have financial problems O_o 

Similar OVAs in that they both revolve around rather attractive women who do detective work relating to the supernatural.