Basic Accounting System in ASP.Net

I am looking for an existing web based or Win forms basic accounting system I can integrate into a custom system retail optimization system. I wish to purchase exiting source code. Must be in c# and SQL 2008. Must be up to framework 3.5 as a minimum. Bidders must provide screen shots of proposed solution. Use of third party controls okay as long as reputable. General overview of accounting features: A) Core Accounting (general ledger, financial reporting, accounts payable and accounts receivable, Sales Order processing, inventory, Trial balance, system side reporting for each area). B) Bank reconciliation and reconciliation of balance accounts in general C) Fixed asset management D) Multi-currency and Multi-language E) Chart of accounts must support roll up of sub accounts F) Inventory must handle LIFO, FIFO, and WAC inventory valuation methods.