Debbie, it will take time and...well...even after you think you know them they go and pull stunts that surprise the bejeezez out of you!

Cats do pick up on your stress and will act out on it, so it sounds like that might be what's happening. Is what she's doing really all that terrible that you have to keep at her? I only ask because maybe the best thing to do would be to just ignore her. Or, another option might be to confine her to one room for time outs when she is naw-tee. This might be the better option because then she can do whatever she wants in that one room so she is less stressed, and you and hubby don't have to constantly keep watching her so you are less stressed.

Even 2 1/2 year old cats have a lot of play in them. MUCH less than a kitten, but they're not sofa slugs by any means at 2 1/2. My only other suggestion would be to get her a playmate - as in another kitty - but I don't know if that would be the best thing for you right now.

Play with her, keep her entertained, get her a cat tree to climb on, etc. But DO NOT just put her outside! That would be the absolute worse thing in the world you could do and would solve nothing. As for being in the garage, there's no problem with that either as long as you know she's there and remove her before moving any of the vehicles. Tubby ADORES being in the garage with his Daddy.

Anyway, if you're all stressed for other reasons, my advice to just have patience isn't very good advice at all, but I know with time she will settle in and you will get to know her better too.