From past experience. I would use services like BigCommerce or Magento Go and charge about $500 to pick a template, implement, and set up. Train the client how to add products and have them add the 50 products.
I suggest going the BigCommerce or Magento Go route because the client might be a headache in the future always calling up and asking questions as to how things work or how to do certain things. Instead, now they would call BigCommerce or Magento Go and directly ask all the technical questions. You can open an affiliate account with these services so you do receive residual income every month.
