How hard to make this game?

[FONT=&quot]Hi,

I don’t have a lot of experience in flash and have only ever done basic things before.

I have someone asking to make a game along the lines of http://www.puffgames.com/pstrip/ - for those who are a bit more experienced is that a huge undertaking?

It doesn’t seem like it would be too hard, bit of collision detection and swapping a few images etc.

From anyone who uses flash, how hard would you say that game would be to build and roughly how long would it take?[/FONT]