2015 Lexus IS250 AWD, 109 000 km (68 000 miles) 2.5 L V6

Hello, I have an internship in northern Quebec from January to April. I'm not usually worried by cold weather being a Canadian but it's a 7h drive up north where it'll always be very cold (-20 to -40+) on average.

Car battery, Brake fluid, Transmission and differential fluids changed last year. Antifreeze checks out (with the ±accurate manual pump and rubber tool).

My future supervisor mentioned getting an oil change before moving up and getting a different 'made for winter' oil. My mechanic said that his 4 season oil should do the job and that my car is recent so I shouldn't have to worry about that (Not the Lexus dealer). So I don't know about that

Should I absolutely get a bloc heater installed (or install it myself if I can figure it out) or get a portable battery booster in order to avoid any possible problems this winter? I know it's a Lexus and I shouldn't cheap out on this stuff, but my budget is tight right now.

Finally,
I'm just a college student, i study in chemical engineering. This used to be my grandmother's car(bought used in 2019), but she doesn't drive anymore and gave me her car. It was rarely used and big neglected to my standards (mostly many rust spots all over the car). I can afford the basic maintenance on it but cannot afford to take the best care of it yet. I've myself done most of the maintenance (and bodywork/paint) since, and preemptive maintenance so I won't have to worry about it until I graduate, i wish (Ha!).

Thank you for your time and have a nice day