With the weather we've seen lately I'm hard pressed to recommend taking a trip like this considering your situation. I'm inclined to agree with what donkeydew said.
Heading I84 around Pendleton, OR you have Emigrant Hill, commonly called โCabbage Hillโ one of the worst stretches of highway in Oregon I'd say. Frequent weather closures along with the semi travel along the highway would make me think twice.
Hwy 20 to Bend/Burns you've got the Cacades, but after Burns you've got a whole lot of nothing - not a good area to have a break down but even worse in the winter months.
I5 South around Ashland, OR you've got Siskiyou Summit then a lot of highway as you head sound once you get to Redding it gets better and less weather issues.
Last thoughts, you're driving a 27 year old minivan and I'm unsure how old your trailer is (the Timberline TT I'm thinking of is from the 70s.) As you've said this is your HOME and you're on a tight budget. You'll need change for both the Van & the TT.
I'd really think twice about this trip during that time of the year.
Two Wire Fox Terriers; Sarge & Sully
2007 Winnebago Sightseer 35J
2020 Jeep Gladiator Rubicon