looking for affordable roof storage system for 09 e70

[e6t]

im getting ready to take the whole tribe cross country and need to be able to put some stuff on the roof of the X5. Currently, I have the factory side roof rails on an 09 and im looking for options without buying a new thule or yakima... The X5 is leased and I only have a little over a year left, so Im trying to avoid spending a ton of money for this one trip.

Have any of you found a good alternative to the big names? I tried a search but after thumbing through 3 or so pages, gave up.

Thanks in advance.