Frank, do you have kids?
If so, do what I always do........blame it on them. :-)
Later, after the wife has settled down a bit slip the son/daughter a $10.00 bill and everything is fine.
Say to the wife; "I don't know what's gotten into that boy.....he used to be sucha a good kid....well.....I should probably take the model and put it up somewhere around my workbench so he can't get his hands on it."
Trust me, kids are used to getting yelled at so if they're gonna make a few dollars out of it they wont mind, plus you get to keep the model.
If you don't have kids to blame stuff on, another good idea is to have a friend or relative to order kits and have them delivered to their houses. When the kit arrives you just go pick it up, slip it into your stash and keep your mouth shut.
Never, ever, under any circumstances buy your wife gifts to get out of the dog house. This is why there is a "dog house" to begin with. When the wife figures out that all she has to do is get upset in order to get free gifts she'll start looking for reasons to put you in the DH. Heck, I knew a guy once that had it so bad he had to buy his wife candy everytime he got crumbs on the floor or left the toilet seat up. After ten years of marriage his wife weighed 400lbs. and the husband was put on anti-depressants.
Hermon