the policy with inghams carrier is 1 ski bag = £15 I have a four ski bag holder and only pay £15. The boot bags can be a problem as they are a little thicker than the alotted size of hand luggage so you may have to put them through as normal luggage. If you feel you need more space do as many others do and get an extra ski carrier and fill it with whatever and pay the £15 as thats cheaper than paying for excess baggage
we took 2 snowboards in 1 bag and paid for 2 carriage but at check in they weighed it said was too heavey and we ended up paying £90 in excess baggage before she would check us in! we got it back when i complined when i got home but they said the weight limit is 6 kg on ski carriage!!!!