$50-60 on newegg, see related link. Alternatively you can lease one from the cable provider, or it may be included in the broadband subscription.
Not necessarily more than the price of a hub, or a router with four extra slots. Check at any PC store for a hub or router.
too much all we do is watch it, around 70 bucks. :(
_`you can't lose your connection to the server easily. _`you can check your server-client rigth away if there is coonection problem accure.
The cable modem can be faulty, check with you service provider