I built a small ecommerce related SaaS over the last month but sadly due to unforeseen expenses I need $1-2k quickly and would need to sell the project.
Searchparcels.com is a SaaS which can be used by Shopify and WooCommerce store owners to provide their customers with an elegant way to track their orders and upsell them at the same time. On the parcel tracking pages can be products displayed which directly link to the store again.
This is an untapped source of traffic and a way to pull customers back in at a low monthly cost of $9.90 for unlimited parcels. The billing is done automatically using Paypal subscriptions.
The site is built using PHP and a Mysql database, the cost to run it is $10 per month for the server and $10 for an external API.