Hi guys now I am liking the AR-15 platform, found online a NIB S&W AR-15 Sport Model just the base model. This gun was a gift & the owner has it up for sale unfired. He must need the cash he is asking $550.00 cash is this a good price?? I keep thinking my Mini-14 is all I need but these AR-15's are very nice.I keep thinking maybe have two .223/5.56 rifles. Comments appreciated & thanks in advance!