Some things to consider for cage size.
Do you plan on moving the cage at any time in the future ?
If so then you have to consider how you will get it in and out of rooms. Most doorways are only about 6.5 ft tall and roughly 3ft wide and that makes moving an 8ft cage pretty rough .... thinking how it will go around corners, ect. Ex .. if you have a tight corner you probably cannot take it thru the door the long way and if its 8ft you cannot stand it on end to get it thru either, that leaves you with a window ... maybe.. depending on the window and where it is - apartment, 2nd floor of a house ect.
I've been planning on building my own enclosure for my Burmese and have been reading the Forum on Cage and Habitat design. There is a lot of good info there but one of the ideas that stood our for me was building sectional cages. You build 2 .. 6 ft cages and bolt them together, then when you need to move just take them apart. Also .. if your snake is small enough at this point to be ok in a 6ft cage then just make 1 and when it gets big enough build the 2nd one and put them together.
But if you never plan on moving the cage or moving from your current residence then theres no problem of course.
Just wanted to toss that idea out there for others who may need it and didnt see that in the Cage forum.
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Pete
1- 0.1 Boa Constrictor
1- 1.0 Patternless Green Burm
1- 0.1 Pueblan Milksnake - Apricot phase
1- 0.0.1 Honduran Milksnake - Tangerine phase
1- 1.0 Ball Python
1- 0.1 Rainbow Boa
1- 0.0.1 Cornsnake - Blood