Bulk Google Sheets Export

I have a collection of Google Sheets sitting together in one Google Drive folder and I need each of them converted into its own standalone Excel workbook (.xlsx). The end files should carry over only the visible values and the existing formatting—no formulas, charts, or images... (Budget: $8 - $15 USD, Jobs: API, Copy Typing, Copywriting, Data Entry, Data Mining, Data Processing, Excel, Google Sheets, PHP, Visual Basic)