I'm a professional and have been doing magic for decades.
Kaps' Currency is in my program any time I'm in a venue that calls for a suitcoat. It requires, in addition to the suitcoat, a suit-style wallet, and a number of dollar bills. There's a tiny bit of prep required of those dollars, but they're still spendable afterward if you need bus fare home. I'm not certain that this would work with plastic money (e.g. Canadian). Performance requires two volunteers. The trick can be done at any distance, from close up to stage. Angles are good. Not really aimed at children, and child volunteers (due to the height difference between you and them, and their perhaps less-than-fluid ability with handling money) can be challenging.
The effect is as stated: no matter what the magician does, the eleven dollars in his hand become ten dollars. The instructions are clear; the photos, while dark, are useful.
I have no conflicts of interest. I'm a professional who has been doing magic for sixty years; primarily platform and stage magic, concentrating on sleight-of-hand.
I built this item, and have presented it in public on many occasions, mostly Halloween shows. I intend to build a second house, using what I learned from making my first one. It's easily portable and only requires one person (you!) to operate. The audience reception has been quite good.
You should know when building this, that doll-house parts (e.g. windows and doors) are not cheap. Getting the opening door and opening window to function reliably was a matter of trial-and-error. If you don't have access to a table saw and jig-saw, construction won't be easy. Please use the thinnest, best-quality plywood you can get! I have easily sunk a couple of hundred dollars into this effect.
I've modified the tricks that happen in the house to suit my style and wrote my own patter.
Definitely a worth-while routine.
I have no conflicts of interest concerning this item. I've been doing magic for about sixty years, primarily stage and platform magic, where my greatest love is sleight-of-hand. I am a professional.
To help y'all decide if this is for you, you need to know that the show requires a primary performer plus two secret assistants (and possibly a stooge). It is designed for performance on a full stage with wings. The ability to control house lights is useful but not required. For transport purposes, the largest single piece is a sheet of hardboard, six feet by seven feet.
The spook show runs for about twenty to thirty minutes. There is lots of opportunity for elaboration.
The text is clear and the illustrations are complete and helpful. Although I have not personally performed it, this is a well-thought-out routine. I do intend to have a version whipped into shape for Halloween season.