I have tried soap making using the melt and pour method, which is easier than the traditional cold process method. I spent around £50 to get started. I bought the soap base, some moulds and some colouring and essential oils. I do quite well selling at markets and craft fairs. I didn't have much luck on etsy and haven't tried ebay, although I got my supplies from ebay. It costs me around £1 to make the actual soap and I sell at craft fairs for £3 upwards.
A friend of mine makes and sells her own jewellery and does quite well on Etsy. She does also do two or three craft fairs a year usually in spring, summer and just before christmas and does very well. I think it depends on what you are thinking of making.
I used to make a lot of handmade greetings cards and stationery which I sold to friends. What type of thing are you thinking of selling? You could start off small by having a few folk round and sell at a party, progress to craft markets and fairs and then test the market at Etsy and Ebay.