When to give it up?

Your door tumblers and ignition are likely a worn out key vs those parts going bad. Try the spare or have a new one cut from the vin.

 

It's not just a matter of what you can buy another truck for, but how much you will need to spend on THAT one once you get it. That's why sometimes it makes sense to put money into an existing vehicle who's book value may not be great, but is up to date on maintenance.

Besides, for me, I got a Gen 1 because I wanted a Gen 1, it's not just about the math.

 

More than likely that needle bearing in the front diff is going out, they were not the greatest in the first place, and yours is probably gotten all the good out of it which lets the inner axle cup run out and make a crazy growling noise you can feel in your feet at certain speeds. You can usually grab the drivers side inner axle cup and wiggle it up and down a lot when this is the case, its not terribly difficult or expensive to replace the needle bearing with the Isostatic Bearing and a new seal and that pretty much shuts it up better than stock/new.
The front tires wearing is likely from a bad alignment, a lot of times people doing alignments on the Toyota front ends, dont adequately tighten the lower A-arm nuts and the weight of the vehicle will cause the lower A-arms to move around in the pockets. Sometimes its just one, the front or rear that wiggles itself loose enough to start moving and this causes terrrible wear to the tires. With the amount of rust you have, you wont be able to get the adjusters out of the A-arms, they are certainly going to be rusted together so in order to actually get a front end alignment you would have to
1) cut the lower A-arms out with a sawzall
2) cut/drill the OEM bushings out of the OEM Arms and push new bushings in the lower A-arms OR Buy new lower A-arms
3) put new adjusters and new bolts in
This is likely the only way you are going to be able to actually give it a front end alignment to fix the tire wear. Yes that involves spending more money but honestly, if you saw the tires wearing a year or two ago you would have been better off fixing it back then before the tires got clapped out. I bought my truck and it looked straight, but the first 5,000 miles or so the right front tire was wearing BAD and doing it FAST. It didnt show a single alignment in its entire life on paper so i pulled it all apart and found the adjusters were rusted in the lower A-arm bushings and went thru the steps above to correct it so i could get an alignment. I machined a nice tool to go in an air hammer to try to push the adjuster sleeves out of the A-arm bushing sleeves but had zero luck and had to use the sawzall to cut them out to get the A-arm out of its pocket.
When doing an alignment, you REALLY gotta get a long pull bar and pull hard on those lower A-arm nuts / bolts and cinch it down big time or they tend to move over time.

The rust i have seen in your pix honestly appears more superficial than anything, sure the fender well behind the rear tire is clapped out, sure the trailer hitch is clapped out, unbolt the hitch and let it fall to the ground. If you have a 2021 that you can tow with, dont worry about towing with the 1GT. The frame doesnt appear terribly compromised but putting added stress of towing a trailer definitely wont help it stay straight, drop the trailer hitch and drive it as a non-hauling truck. I assume you fixed the gas tank stuff from a year or two ago so it doesnt leak when you fill it up? I mean i would get all the life out of it i could, i certainly dont see why you would throw it away when the things that appear bad are cosmetic and superficial. If it runs, rock and roll.

 

Thanks badass03taco!

 

Yeah I agree with this.
Everyone says to get a new vehicle when repairs cost more than KBB or replacement cost...but imo it makes more sense to consider what you would replace it with first and then compare the monthly cost or total cost.

Like I have ~7k into my 03 (4.5k purchase + repairs) and it's basically a junker outside of having a great frame.
7k upfront is just over 12 months of $500 payments.
If I dropped 7k as a downpayment into a new truck, I'd still have 60 months of higher payments for anything else...and then remember taxes and registration and insurance and you'll still have repairs to pay someday

If you're like most of us on this forum then doing your own repairs and just babying stuff along can get you a looong ways.
Is it always worth it? No, but it's more nuanced than if $X>$Y