How do you unlock the locked houses?

For the Goth manor you have to complete the Nine Lives mystery challenge,which you need a cat for and the cat has to have hunting skills. For the other locked house, I believe you need your cat to get rid of all the ghosts in the house, which also requires your cat to have hunting skills. Good luck!

You have to catch 25 spirits for the house on legendary lane

Where do you find the spirits

Invent the ghost catcher thingy and when you get the note in top right saying a house it haunted go catch the ghosts

If you get rid of 24 ghots you can see a thing on top and it will say you unlocked on you're screen...I can't speel srry idk y

All you have to do is buy a inventing table and a sim has to keep inventing things on it until she/he gets the goast zapper. The goast zapper is not the same as the goast positioning system.
If you want to unlock houses you have to go to the map at night and you should see little icons
With goasts on. Go to that lot and get all the goasts or sprits. They should be hanging around that house.
The house shold be a foggy too. When you collect, I think 24 or 25 goasts from the same house you unlock it.If you want to unlock gilman manor you have to complete the challenge nine lives. To do this sign up for the mysteries challenge thing at City hall and thats it. I hope this helped ;D

Ok for everyone who think it's 25 it's 24 secondly it spirits and ghosts put together third point is you can do it with a ism as well NOT just a cat it's easier to do it with a cat but a ism can do it to that's for legendary lane and by the way it's the Goth manor not the Gilman manor and to unlock that one you need to complete the entire mystery chapter of just nine lives to live to do any mystery register at the city hall so my points have gone across 😄😄😄😄

FOR GOTH HOUSE
Finish nine lives challenge from town hall!

OTHER HOUSES
Catch at least 25 ghosts in a house
The house will be foggy
You can catch them by inventing a ghost zapper from the table in skills section

How do you unlock houeses that are locked in The Sims pets 3 for ps3? I would really like to know

To get the locked houses, first visit town hall and register as a misteryoligist (forgot how to spell it) and go to the mystery book. For the goth manner, you must have a cat and complete Nine Lives To Live. For the other locked house I believe you must clear out the ghosts like the goth manner. Hope this helps!