Vendor/supplier availability

I understand how to import vendor price lists, is there a way to import vendor availability at the same time, this would be a weekly task for 100+ vendors, possibly something that they could do in the vendor center? We would like to show our customers qty available (with constraints per vendor) that would be close to accurate. A specification of inventory would be helpful too. For example: item #, cost, #avail, specifications-quality & size (23194, $20.34, 302, 3'tall x2'wide *prime).
The available # would not act as inventory (accounting), but would default to a vendor that does have this in their inventory.

Could we also assign vendor and cost when creating Estimates, it is sometimes difficult to track what price was given by what supplier at the time of estimate.