I have parents like that and I've been smoking for like 2 years.
Some tips:

1: If they ask about money the best excuse is to say you spent it on food/paying friends back because you wont have to produce hard evidence if you lie and say you got a new cd ect also getting a job is good too.

2: Your parents asking where you are isn't that big of a deal, you have a few choices
1: lie and say you went somewhere you really didn't
2: Just tell them the truth; often I'll go somewhere to smoke like the park and Ill tell my parents I'm going to the park with my friends, after all its not like they are going to follow me.
3: you can also tell a half-truth of some kind (be creative).

The best thing you can do after getting high before coming home is to just not come home until your sober, otherwise if u absolutely have to be home while your high bring clear eyes, Axe and pray to god.

Often I sneak out to smoke after my parents are in bed I find it works great and you have the whole house to yourself, here are just some tips:
1:Make sure your parents are asleep obviously
2: If your parents are gay and make a habit of randomly getting up at one in the morning to check on you then sneaking out is a bad idea.
3:dont go too far away from your house
4:dont be loud

Hiding my weed has never been that hard because I'm into Legos so I have boxes upon boxes of legos that my parents know better then to touch so I just hide it among my legos.