Great stuff Nippy, sometimes you can read the first couple of chapters free, and then you can decide if you fancy buying the book

Well done Nippy, good luck!!!

I don't have an actual Kindle device but I do have several devices with the Kindle app which is virtually the same.

The cost varies just like real books. I have many free books. Others I paid for. The Kindle version of a book will be cheaper than the regular book though.
Yes you have it forever. You can download it or keep it in the cloud but it's yours to keep either way. I like that I can have so many books this way. I have so many real print books as it is that it is now great to have ebooks. I never thought I'd get into ebooks but I sure have, very convenient.
Amazon is where I get the Kindle books. I also have Google books and Kobo.

I resisted the Kindle for a long long time then hubby got me one to try it out. Now I wouldn't be without it.

I've got boxes of books up in the loft. It would be so much nicer to have them all together on a machine that a couple of clicks gives me access to rather than having to get the loft ladder down and go mountaineering