They leave poo everywhere, and they throw it, you can't have a drink when they are out of their cage unless you don't mind chinchilla poo in your drink.
On of mine had a leather fetish, you would hear a donk donk and he's have found a watch and was taking it home.
Mine got in to the kitchen, went behind the cooker and chewed through the cables.
They chew the corners of walls, your skirting boards, my friend's skate board.
You have to really look after them in summer because they are susceptible to heat.
Their poo gets everywhere, I know I have already said that but you open your purse to pay for something and there is poo in there, the cable TV guys comes round to fix your cable and the problem is chinchilla poo - three years after they have passed away.
I loved having them and I got them from a rescue, and I did a lot of research but really you need to have a 'chinny room'
And it needs it have aircon.
If you look at posts on here you will see I'm often up very early in the morning so they did get hours out of the cage to run about and destroy my home.
I loved watching them do a wall of death run around but they are a huge commitment, they can live 20 years.
Another vote for rats or mice. I had the latter but know a few people with rats.
My mice were handled from new so were quite well behaved (even the vet was impressed) they are very entertaining, when you clean them out if you rearrange their cage they get excited about it.
I used to put some food in a cardboard egg box and they would tunnel in, when you opened the lid you would have a mouse in each 'egg space'.