not sure if I’m too late for this – but I’m in the uk – I bought a heavy duty cake box that’s very deep (takes at least 4 tiers) with a special cut out in the bottom for round or square cakes its not cheap about £16.00, I also lend a nonslip rubber mat for transportation I always ask for the mat & box back and have been lucky so far that they have always been returned – here is the link – they have handle holes
http://www.thegreatcakewarehouse.co.uk/transportation-boxes-133-c.asp
