There is no simple answer to your question....depends on your performance requirements and budget. Pick a few vendors and look at the pricing. For flexibility in a growing business AWS is a good bet via TKL Hub or direct via AWS console. (Disclaimer: I am not affiliated with TKL, have not used TKL Hub, am not affiliated with AWS, am an iiNet vCloud Director and AWS user). If you go AWS you will need to consider reserved instances to keep the price down (a small instance with a 3-year $200 up front spend runs at about $15 / month for  low load site which is $20 / month over the 3 year period...cheaper in some regions other than Australia where I am).