Hi Zoo! This is an excellent tip for builders. I NEVER build without a sim on the premises. It is so much better to play test as you go than wait until the very end. Also, having a sim with skills can come in really handy. I finally got a sim to level 10 in photography and it opens up a whole new avenue for wall art - just remember NOT to put them in the digital frames or they won't transfer. The same with having a painter sim.
As far as assigning traits, you can easily change them out as needed by using "testingcheatsenabled true" and shift clicking on the active sim. You should get an option to change the current sim's traits.
Also, you don't necessarily need to cheat up your reward points to get SOME of the reward objects. The hover bed is available in buydebug, as is the teleporter and several others.
Oh, and one other good reason to have a sim on site is so you can take photos in live mode using cameraman mode.
And finally, I have the sim cancel newspaper delivery first thing so I don't have to deal with newspapers littering the place.
