Several years ago, my husband was still in grad school and I was unemployed, and I started making plush. In part it was to help combat depression (colors! soft fabric! huggles!) but it ended up growing into an online business selling high quality custom plush. I sold my works usually for ~$200 USD, but my highest sold for over $500.
I'm going to try and answer your questions in order, but with extra advice at the bottom.
1. Frankly, I wouldn't pay $200-300 for a plush either, especially now since I have the skills to do it myself. But one look at the fanbase and it's clear there are a lot of people with disposable incomes who are looking to buy something they can't get anywhere else. If your work fills a market gap and it's that high quality, you don't really need to "persuade" anyone; they find themselves attracted to you. Of course, gorgeous pictures and high quality product contribute to this.
2. There's no reason to spend money on marketing when you have most of the internet. I personally used DeviantArt to post my work and build up a fanbase. Most of my sales were people who found my work there and wanted to commission me. Etsy and other online markets can broaden your exposure, but you also have to stand out from the competition.
3. I'm sorry to say, the answer is "trial and error". There are some artists who are so good and so in tune with the market, that what they "do what they like" and the masses go nuts. Usually these are people who already have a pretty strong backing and fan base. To start out, unless "what you like" also matches "what I like", I probably won't buy from you. Especially with your up front costs, I'd urge you to consider the first batch an experiment. And if colors are anything like spritelings, black, blue, and purple sell like hotcakes, while yellow and orange are less popular. Since you're doing accessories, maybe having images of scarves paired with outfits would help attract folks who aren't as good as composing a "look" themselves. You will definitely need to experiment.
4. I did both. I found Etsy was better for selling general items or when your advantage is to reach a wide market (i.e. unique product, lots of exposure). The more niche you are, the more you need to develop a fanbase. I personally used DeviantArt and just had people note me for commissions, but I'm sure there are other platforms. 50% commission is rough, but again, if selling 2-3 in a store can help get your brand name established and folks directed to your website, maybe it's worth it. I wouldn't personally encourage a personal shop off the bat, because you need to direct traffic to it. Until you get people to start looking for you, another webpage may not help much. Focus more on selling a few scarves than building websites or marketing.
5. Oh geez. Everyone does it differently. Some pick an hourly wage (is your product worth more because you're slow?). Some base it on where in the competition they want to sit. There are whole articles and long conversation threads about this. When I sold, I was basically the affordable of the good-but-not-OMG pack. I needed to earn enough to pay the bills.
6. Since I made lots and lots of ponies, this came up. I used two basic strategies. One was the variety of colors, shapes, and hairstyles really helps. One day it's green and purple, the next it's black and yellow. Having small customizations really helped keep me interested. And two, probably most important, was I always had a side project for myself. Sometimes this was something I sold, sometimes it was something I kept for myself. But if I felt frustrated or burned out, there was *something* I really wanted to go make, and I could work on that instead.
7. Yes! It is very hard to enter a market near the top end. There were only a few plush makers who could do it, and their skills were beyond amazing. But there are also very visual cues to quality and skill when making a plush that are easy for the audience to see. Are there similar markers for silk scarves? For instance, I ran a quick Etsy search and there are scarves (with gorgeous colors!) in the $50 range, and others closer to $150. What sets them apart? Granted I'm no expert, but at a glance it's hard for me to know what warrants that price difference. The first plush I ever sold was $15 (to be fair, it was also just about the first one I made, and a test, but still) and moved up from there. I bought a used machine for $60, but the profits from my first few ponies bought me better materials. TBH, I found that if you enter "to make money", it's a disheartening and frustrating experience. If it's an educational and growth opportunity, it's a lot easier to weather the rough parts.
I've also seen a ton of people burn out on chasing attention/market share/etc. People are fickle, and always trying to race to the next big win is hard. Starting out, I think it's a lot easier to sell a few pieces, recoup your costs, look at new techniques or tools, and get a better sense of what people want. If you make something beautiful, others will want to commission something similar. Especially if you make a run of 12 identical scarves and you only sell 1, that's a rough place to start. "exclusivity"/limited edition is more attractive in high volume or high desirability items; when you're just starting out, does buying one of only 12 in the world make a difference? I sort of expect a lot of artists to be making one-of-a-kind, or a wide variety of options, rather than the entire stock being 12 of one exact item.
And pictures. Pictures are everything. Take time to read some articles. I personally like this one (
http://fav.me/d6klbb8) as a really simple starter. Gorgeous products are hard to sell if the picture doesn't show it off. There are probably facebook groups or forums talking about these kinds of things, or even silk accessories in particular, which might also have some Q&A from other people.
Keep in mind this is all just one person's advice and perspective, and plush making certainly isn't a 1-to-1 to clothing. But I hope it helps, and I hope you do well with your side project!
