Forum Moderators: buckworks
Multi-currency is common but it is rare for the prices quoted to be actual prices, they are normally indicative prices obtained by using current exchange rates - the final price paid will be determined by their bank and VISA or similar who will handle the conversion. A major exchange rate site offers reasonably priced feeds which you can use on your site.
The main exception for multi-currency is where you are massive and have a physical international presence or you are using an international payment processor capable of native handling for multiple currencies. In the former case then your local branches will need to determine appropriate rates and billing; in the latter you will either need to supply all prices in your base currency for processor conversion; or sometimes to supply prices in foreign currencies yourself to be billed at those rates.
I was just at a store where for each item in the shopping cart it said "shipping from our california warehouse' or 'shipping from our #*$!x warehouse'.
As long as shipping cost is just one amount and not broken into 2 shipping costs because of the 2 warehouses, I think it doesn't get complex at all.
The best way would be just to combine the costs if there are 2 warehouses.