Question: Where to start?

Hi! My name is Ashley, and I am very excited about the possibility of getting my own axolotl. I absolutely adore the little beasties, and have ever since I saw one for the first time in a museum. However I do not want to jump into such an endeavor uninformed. I would never intentionally harm any animal, and I really want to do my part in being a responsible pet owner.
I have done as much research as I can think to do about the following topics. Please correct me if you take issue with any of the points listed below, or if you know anything I missed!
Please also note that this is my first post on this forum. I'm not sure if this post really belongs someplace else... Oh well.

Where do I keep an axolotl?

Tank should be between 10 and 20 gallons per axie
Sand or bare glass is fine
No gravel (they eat anything and everything)
Be careful of plants
NO TANKMATES
Besides other axies
Below 75 degrees fahrenheit
My space is 70 degrees year round, also fahrenheit. Is this too hot?
The less light the better
My space is pretty dark. There is a window nearby, but it is always shuttered.
Does turning on lights suddenly bother them? (just thinking out loud)
Keep a lid on it!
Filter should not disturb the water too much…
...Axies get stressed easily.
Hidey holes are a must
Water should be treated-- tap water is fine if treated properly
Tank should be cycled by 20 percent a week.

How do I make sure my axie is happy and healthy?
Observe poops.
Clean poops with turkey baster! They’re pretty cheap where I live, so it’s not a problem.
Axies poop every 2-4 days if they’re healthy-- may vary some
Green poops are bad
Some poops may disintegrate
Totally normal

Feeding:
Once a day (?)
Use food about the same size as their head
Earthworms, bloodworms, blackworms, salamander food pellets all okay
Squishy pellets work better (?)
How much do I feed them?

Behavior:
Varies with temperament, but…
Older axies move less
Babies move lots
Sick axies may not follow typical behavioral patterns
Avoid light and stick close to hidey holes
Stressed axies will develop curved tails and pale in color. They may also stop eating.
Please tell me more about stressing axolotls!
Axies live to be about 10 years old (8-12 is typical)

I probably missed something, but these are the basics of what I’ve learned. I would also like to know if hamster/gerbil accessories are okay in axolotl tanks-- and if only some are, how to tell the difference. I really want to have pink sand with a little strawberry shaped hide alongside some pink plastic plants. However, I do not want to do this if it will in any way endanger my little buddy. His or her wellbeing comes FIRST.
I will also be handling non-toxic acrylic and tempera paints nearby. Will my little baby be okay with this? I don’t paint often but my hope is that once I get the space cleaned where he or she will go I can start again. I can’t think of a better muse, after all. Wouldn’t cute chibi-style axolotls on the walls really make the space?
I really don’t know much about testing for water quality. I know that ammonia = bad and that I need to change the water by 20% weekly, and of course, that poop needs to be picked up. Are there any testing strips available in USA that anyone recommends? What should I look for with these strips? How often do I test the water?
Lastly, but certainly most important, are axolotls legal in Oregon? A year or two back I saw some in a pet store, but laws change over time. I have checked the local Wildlife Services website and I have not found anything regarding the matter.
Thank you all for your patience, time and support. This is very important to me, and I cannot express my gratitude enough.

Hi Ashley! There are a few things here that I would correct... Axolotls should never have their water get up to 75 degrees. They should be in the low to mid 60s. It sounds like your room will be too hot if it is around 70+ as it runs the risk of fungus and other issues. You can always buy an aquarium chiller to help.

They also do not eat every day when they are adults, mine are every two days or so but it varies by axie. They eat more when they are juveniles.

For water testing, I recommend the API Master Test Kit. In my experience, the strips are inaccurate and therefore useless.

First things first: Cycled tank. This means your filter is nitrogen cycled and colonized with beneficial bacteria that turn your axie's waste product from ammonia to nitrate. The nitrates (and trace ammonia and nitrites) are what you get rid of every week with your water changes. I do about 40-50% every week, but that's just me. I also recommend STAYING AS FAR AWAY AS POSSIBLE FROM CARTRIDGE FILTERS! They SUCK SO BAD! You have to get rid of ALL the bacteria EVERY time you change out the cartridges, which you HAVE to do because of the stupid carbon they put in it instead of bio balls or something. Carbon DOES absorb stuff out of the water and helps it get clearer, but after a while it leaches the bad stuff back out into the water, so you HAVE to change it. I don't run carbon on my tank. You don't need it unless you're medicating. If you want a hang-on-back filter, go with Fluval. Trust me. If you don't want a hang-on-back, get a sponge filter without carbon. You NEED water conditioner (I LOVE PRIME) and a water test kit (API's is great. I don't trust the little sticks). The conditioner will quickly convert the ammonia in tap water to nitrate/nitrite, and it also gets rid of any chlorines and fluorides in the water.

Water temp: I have a fan for my tank (axies like temps between 60 and 68 degrees Fahrenheit. I got it for like $30 off amazon. Just look up aquarium fans.

Low light: KEEP THE TANK AWAY FROM THE WINDOW. The sun can heat up your tank through the window, and the sunlight also encourages algae growth.

Your feeding pattern will vary as the axie gets older. Young axies=fed every day, older axies only need fed like once per week-every other day depending on their metabolisms. My dude eats like twice a week to maintain a healthy weight.

You also want to be careful of pairing axies. All axolotls are cannibals. They will eat at one another. This is an unavoidable fact. If you want more than one, you need an extra 10 gallons or so per axolotl. I keep mine on his own in a 30 gallon tank, and he uses every single inch of it.

They're extremely personable, and get attached to their owners. You have some awesome research done, and I look forward to seeing your new baby!