-no you're not committed to buying bundles. You can cancel any order even after you've made a payment as long as its not been shipped.
-free post is an error made by the seller. They will either honor it and cover the cost out of the price of the item you've bought or cancel the sale and relist it with postage cost once they've realised their mistake.
-when you buy an item you will be updated when the item is shipped, in transit and ready to collect. You have a limited amount of time to collect the item (I think it's something like 5 days) so you could collect multiple items at once as long as they were purchased around the same time.
-you can offer multiple postage options, the buyer will then select which one they want to use or just select the one that suits you best. I like using evri.
-if you ship with evri vinted will send you the label to print and shipping instructions to follow. It's very straightforward. When you drop the item at the shop it's scanned and automatically updates on vinted with a tracking code. You can also take a photo of the receipt they give you and send it to the buyer.
It's really is quite straightforward once you get into it. Vinted does guide you through it all step by step.
My advice is to take lots of photos of your items when you list them, include any faults on used items. Take a photo of item packaged for your own records.
Iron clothes before you take photos.
Use Hashtags in your item description eg #lightweightjacket. They'll pick up people's searches.
Price items realistically but with room to accept offers.
Engage with your buyer, tell them when you'll be posting their purchase, be polite, apologise if its late etc. You'll get good feedback which helps future sales.
When you buy always make a lower offer 1st. You'll be amazed at how often they're accepted.
If you favourite items sellers will often then discount it.
Don't spend money on packaging. Use carrier bags turned inside out. As long as they're clean and well sealed they work really well.
It's really good, I've had some absolute bargains and I make around £50 a month selling DC old clothes, trainers etc.