Hello, best snake for me?

Hello! I am new to this site after being a long time lurker.:P After not being able to receive specific answers just by looking at old threads, I decided to make an account, so here I am! I am really wondering about what is the best snake for me. I am a responsible pet owner who will take care of it for the WHOLE it is alive, whether it's 3 years or 30 years. Some things I am looking for in a snake:

Docile

Medium size (5-7 feet)

Not too skinny ( I like a bit of girth)

Not too expensive ($200 and under)

Cage no bigger than 4' x 2' x 2' ( I am looking at modifying a christmas tree tub- seems to be the best and cheapest way to go)

Although I am perfectly aware that snakes can be unpredictable and bite, I would rather it not be something that is know for being aggressive/ defensive (like GTP and ETB)
I myself am fine with being tagged a few times, as I know that is part of owning a snake:)

The three options I have really looked into are:

Dumerils boa (probolly my #1 choice)

Carpet Python (jungle or iran jaya)

Columbian BCI (male- how big have you seen males get? I have heard contradictory things.)

Thank you all in advance:):)

I've been doing some research on Dums since I'm thinking about getting one and can tell you that they tick all your boxes. Honestly everyone I've talked to that has one seems to be in love with them.

Dumeril's meet all your requirements easily, as a whole and for what they're known for. The other two species can too, but it depends more on finding the right individual, especially in carpets, than it is "as a species".

Dumeril's rarely reach 8 feet, even females (of course there are outliers though). The average seems to be between 6'~7' for females, and smaller for males!

Your gut seems to be leaning towards dumerils so that's what I'd choose. They're gorgeous critters that come in a wide range of colors. I personally dig the lighter animals but they all look nice.

I can tell you from experience the Carpet python and BCI are easy beginner snakes so far. I say so far because I am new to snakes and these two in particular are still young and I've only recently had them. My boa so far has been excellent. He is very hissy when in the tub but once removed he is very docile having not even struck at me once. My Jungle Carpet was very, very nippy the first few weeks and I was bitten repeatedly. She is still very nervous (still a tiny baby) but I have noticed her nervousness has no longer led to bites, she now head buts and prefers to escape. I try to handle her as much as possible and will relax fairly quickly so as long as I make no fast movements or movements over her head. So far the Jungle Carpet is my favorite and I am excited to grow her into and adult tame Carpet. If you don't mind a few baby bites, I would say the Carpet will definitely be more exciting than the BCI, I can't give an opinion on the Dumerils boa as I don't keep this species.

Carpets are my favorite snakes to keep. Every keeper should have at least one :).

Dumerils is going to be your best bet. I have all 3 of the snakes you listed the dumerils is the easiest to take care of as far as requirement. They don't need high humidity, don't need need high temps and generally don't hide much. They are fine with 40-60% humidity, 88F hot spot and around 75-79F ambient/cool spot.

Although as for favorites, toss up between my retic, bci boas or dumerils. They are all loungers except Caesar today who was kind of cranky and didn't want to sit on me lol. He went and curled up under a pillow and sat there. He just shed so I'm figuring that's why he was cranky lol.

If you are going to do a carpet, I have been told Bredli and Inlands are probably the most laid back. Been told by a lot of people that jungles are always a little higher strung. My JCP was a terror when I got her. She still will bite at the drop of a hat if startled. She does eat like a horse though. She's about 3.5 ft and eats a small F/T rat every week.

Wow, thank you all so much!!! I won't be getting the snake for a long time, so I'll have plenty of time to research :)

I was thinking about this tub: https://www.walmart.com/ip/IRIS-Holi...#about-itemand than cutting a 3'x 1' hole or so and putting some glass in there for better viewing. Does this sound like a good idea? Thank you all, you have been super helpful!

I have four snakes - a normal ball python, a Hog Island boa, a young, female jungle carpet and a young Brazilian Rainbow boa and love them all for different reasons. The ball is just so laid back and easy to deal with (except fasting). My Hog Island is two and a half years old and almost five feet - great guy that likes to hang out on the back of our dining room chairs (hunting, I guess). My jungle carpet is a little over a year and can be a bit aggressive but never bites and is generally a great little girl. And my rainbow is such a spectacular snake - beautiful, strong and eats/sheds well. I couldn't pick one as my favourite because they are special in their own ways. The boas are going to be big guys but easy to work with. I'm not sure what to expect from my Carpet as she is long but skinny. I bought these snakes because I didn't want huge snakes that I could not handle on my own (it can be scary when the Hog wraps around my neck and squeezes when I'm moving him around, indicating to me that I can't hang him around my neck much longer).Snakes are such interesting animals!