I'm hoping to start an online shop, selling toys for babies and young children. The plan is to sell a curated selection of high quality, beautiful and quirky items, rather than a vast selection of commonly found items, iyswim. I expect item prices to range from around £8 upwards, with most items costing in the £12-25 range.
I'm really excited about it, but have never run an online business before, and my only experience in retail is as a Saturday assistant 20 years ago! Though I do have a lot of experience of buying.... 
I'd be really grateful if anybody with experience of running an online shop could help me out with the practicalities, especially the pitfalls.
One question I have is with regard to finance. Is it possible to get a business loan for this sort of thing? Do manufacturers/wholesalers do sale or return?
How long should I expect to run at a loss before making a profit, assuming I have a good selection of items at good prices and I market the business via SEO, Adwords, Twitter, Facebook etc?
All advice v welcome!