oscommerce wrk done urgently

oscommerce site have to customize in urgently Depending on which supplier, determines what kind of shipping is available. Only UPS Ground from one, multiple shipping methods from the other. Depending on which supplier, determines which ZIP code products ship from. One from UT, one from CA. Customers should be able to purchase from one or both suppliers. Website should be able to apply shipping rates from both origins to one order. Tax needs to be charged for orders made from CA or NV, with their respective tax rates. Need Someone Expert to Fix this. As i said i need Fix not a complete site. So please Bid Reasonable price. Milestone will be paid Only After Some work and not before. Want to start ASAP.