Backlinking is a good strategy as a part of SEO, for better visibility i may suggest for Adwords, Social Media Marketing, and Guest posting.
Above method also works to get better visibility.
Agreed! :D
There are many providers who can provide affordable services for much lower prices, and nowadays most of the providers offer "Money back guarantee"..
What E-commerce software you plan to use?
For E-commerce website i suggest you to go with VPS/dedi depending on your site usage, You will have full control over your server and your website.