Yes, yes and yes. However, if you're wanting to do this on a commercial level (even at a small scale) there are considerations of "high availability" that you need to consider and the fact that you're asking these questions says to me that you're pretty new to the requirements of servers.
With regards to giving support my suggestion is to go with someone local that is able to look over your setup and will know your DSL provider issues etc to start out. I know in learning all ths for myself I cut myself from the internet a number of times and such a circumstance could end in a boatload of trouble if you're contact is remote only. If you want to have a conversation outside of ASC though that points you in the right direction you should be able to find me by Googling my name… my tiny blog might be of use to you regardless.