I went as a normal sim. I set up on the empty lot next to the Bunch house. I gave my sim a bedroll. I did not build a thing on the lot at this stage. Can't recall my traits at the moment off the top of my head, apart from the handy trait, I probably also gave him the bookworm trait. I also can't recall my sim's LTW. (I will check both when I'm next on my simming computer.)
I sent him next door to harvest fruit from the Bunch front yard (food), and then off to undertake a class in the handiness skill and then sent him to the library to read up further on handiness. After getting handiness high enough, I went and did what upgrades I could in the library, sleeping in the sleeping bag and eating the fruit as my needs dictated.
After I repeated upgrading items around town in other public locations (going for as many unique upgrades as possible), I joined the fire fighter career. I spent (wasted) time in the career, actually fighting fires, but it meant I became friends with people and was invited inside and could do quickish upgrades inside their house.
Once I had been around town and did all of the upgrades I could do without having to purchase items to be upgraded (and also was high enough in the Fire Fighter Career to do all the fire station upgrades), I resigned from the fire fighter career and returned my sim to my home lot and purchased what items I needed to do further unique upgrades - fireplace, stove, umbrella, dart board, bowling lane, water trough etc and did those.
I referenced
http://sims.wikia.com/wiki/Handiness in my planning and playing through of this challenge.
In other files in Sunset Valley, there had been two alien crafts in the parking lot of the police station. Unfortunately, they weren't there in this game file, so I couldn't try to do that.
