Hi all, we have a 6 year old who now has a geared bike so we'd like to increase the amount we're using our bikes. We need to install waterproof storage in the front drive for the 3 bikes and given the cost, it needs to be right, so thought I'd see if anyone has any tips. 2 main priorities are that it can't be easily broken into and that it's really easy for my son to get his bike in and out of every day for school. Thanks in advance.