What construction "Kit" to get.

[FastEddy]

Its time do do a build. (NOOB)
Im looking for a kit that is fully functional.
Im a highly skilled kit builder but not good at DYI fab.
Anything that moves dirt is cool. My eye has a backhoe in mind but the dozers are sweet.

Suggestions on a KIT that is challenging would be grateful.
Im not familiar with whats good and whats not, where to buy, or the going prices.

Thanks,
-Ed