100watts is about the limit in an AC/DC charger, there are a few with more, but they are very expensive. The Passport Ultra has a 100watt internal PS and the effective power available for charging will be less than that due to the inefficiency in operating the charger, it's usually listed as about 90watts of effective output power.

If you're serious about the higher cell count lipos, 4S - 6S, you should consider a DC powered charger since both 5S and 6S lipos will run into current limiting with a 100watt charger due to its output power limit. A charger like the Passport Ultra will charge 5 or 6S lipos, but the reduced charge rate will make for longer chare times than a full 1C type charge rate would have. You can get something like a 106b iCharger with 250watts and a 10amp max charge rate for ~$100 and a 350watt power supply for ~$70 for just a little more than you're budgeting. T