Welcome to Orchid Board Alex!
You've asked a question that isn't easily answered. But it's very wise to ask first, instead of purchasing and then having an uh-oh moment. Growing "orchids" isn't quite like growing tropical houseplants, because of the huge variety of different cultural requirements depending on the particular genus or even within genus.
You say you're a "beginner" at growing orchids. The easiest way to approach it is research each orchid you want to purchase that matches your present particular environment and culture to see if it can be grown in what you already provide for your plants.
Are you willing to provide a different environment and culture for different orchids? If so, you need to research each orchid and see what it's needs are, and whether you are capable or willing to provide them.
You have three dendrobium that appear to be doing well. Are they nobile or hard cane? Dendrobium is a huge genus and you have to know which particular Dendrobium you're growing to provide for its cultural requirements.
The three Phals you shouldn't have much issue with. They're all hybrids, and fairly easy to grow in most normal household conditions. Just research general phaleonopsis care.
The Gomesa Sarcodes is a relatively newer species found in early 2000's. You'll have to research it in one way or another. It's a hot to warm grower and requires a higher light, but I won't get into specifics as I haven't grown it.
Maxillaria variabilis is another species, and is one that's tolerant of extremes. Anywhere from 45F to 98F, but it likes it on the warm side better. Temps provided by KingKong don't appear to be accurate at all, unless my centigrade to fahrenheit converter isn't working.
Sinninga is a gesneriad, relatives of African violets, gloxinia, etc. It isn't an orchid though. That one I've grown in a terrarium with success.
I'd never heard of Dischidia Rafflesiana, and I took a quick look on google search. Interesting plant. Epiphyte, but not an orchid. Sounds like it involves ants? Hmmm, not interested. I have trouble keeping them out of my house as it is.
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To make a long story short, after researching, choose a few with similar requirements and learn how to grow them, THEN branch out to something different once you have a good grasp of the first ones you choose. You'll save a lot of time and money that way.