Welcome Nora. I am a nube here myself.
The initial, limited carfax is free I think. They bait you with a really limited mini report and say there are this # of records you could gain access to if you paid for the full report. Well let me tell you I dont think car fax is worth anything if you already bought the vehicle and its not worth too much before hand either.
It does not list repairs - even ones that are computerized at the dealerships.
It is quite often out of date - I just got a 2007 Mustang used and the car fax said no open recalls and when I checked with Ford there were 2 that had been issued a year prior that it still had not had done. There were also TSBs on it for sticking e-brake and bad water leaks that needed to be addressed so my (new to me) Mustang GT with 12K miles spent a week at the dealership after I bought it getting stuff taken care of. Luck for me I found out all this stuff online at ford and the forums and was able to get it taken care of right off under warranty.
Car fax really only tells you how many times a car changed hands through motor vehicle and how many times it went through emissions testing.
It will tell you if your car was in a flood, been scrapped, etc. - all of which it only shows if it was reported to motor vehicle and noted on the title, meaning you would know by checking the title anyway.
It will not tell you if your vehicle has had a million repairs done on it, if the same problems keep coming back over and over or if its in good operating condition or if it will be dependable and those are what counts most.
CarFax - a waste of $20 IMO but if you are curious about your truck's story and think carfax will shed light on it then maybe its worth $20 to you.
I am on the east coast and the furthest west Ive lived is KC. I hear WA state is nice and maybe some day I will get to check it out. Oh yeah, congrats on the low mileage truck.