Enclosure openings are a matter of personal taste & experience for what you're comfortable with. I've used sliding doors & yes, they have their problems, but for an aggressive feeder, you can also open very slightly to offer prey to the snake inside, without being a big target yourself. Honestly I prefer top opening tanks, but that's me, lol. And yes, that was even for the big snakes including the BCI I used to have (she was 7.5- nearly 8').
Not so sure about top opening tanks, as I'm not too sure on how it'd work with my build. Planning on more of a large rack system.
Quarantine also means being mindful that YOU are also a "vector of disease"- ie. able to transfer pathogens on your unwashed hands & clothing between your snakes. And NEVER re-offer food between snakes when one has made contact but decides not to eat. This comes under the heading of "good overall practices"-
And mites are also a vector of disease- so make SURE there are none while the new snake is quarantined. It takes time for mite eggs to hatch.
Yes! I'm staying mindful of when I've come in close contact with her or her tub, and I will not re-offer food to my other after shes even seen it. Saving a buck or two is not worth the well-being of my other snakes, lol.
And not to be paranoid, but remember that some diseases can "hide" in boas for far longer than pythons- where the boa is an asymptomatic carrier that may never even become ill, or at least not for a much longer time, but which could decimate other more sensitive species (pythons). So the length of your boa quarantine may depend on how you feel about any pythons you already have.
I have one Royal Python (my other snake is a plains hognose). The Royal is thriving, but even when Scarlette is moved into her official enclosure they will still be decently far away, despite being in the same room. If this is an issue in the longer run, anything I should watch for? Would 90 days quarantine be enough if I don't notice anything?