Gloom- which expansion should I buy

I've played Gloom a couple of times now and usually when I am playing a game there is 5 of us and when I saw there were expansions I was so happy. So which expansions would you recommend to get first? And are there any new rules or anything different in the expansions?

Which expansion you get depends on your group. Unhappy Homes adds another family (the Delacroxs) and adds Residences and Mysteries. Residences are part of the family, except instead of Modifiers being played on them Mysteries are played. And Residences cannot die and their points do count for determining victory.

Unwelcome Guests adds another family (the Malones) and Guests, which are like family except they follow certain icons (Lucre, Beasts, etc.). They can die and score points and have special effects on them. The thing to remember is they are not fixed to a single family and can move if they get a better offer (their icon comes up.

Unfortunate Expeditions adds yet another Family (the Bumpersnoots) and Expeditions). There are four Expeditions (Red, Yellow, Blue, or Green). The Modifiers in this set have a colored ring around where the third Story icon that relates it to the appropriate Expedition color. If that Expedition is active, there is an additional special effect.

I would suggest Unwelcome Guests and the Guest mechanic is interesting as just when you think you end the game, a Guest can appear.

Great thank you and thanks for the explanations too

Glad I could help.