The store has been on a decline over the years with the loss of car parks nearby and an increase in traffic making it hard for customers to get to it, Grant said.
It has gone from being open as much as three days a week to just the Saturday (10am to 2pm) and its revenue has dropped to a quarter of what it once was.
If any of the volunteers from the past wanted to come in for a coffee their last chance would be this Saturday, Grant said.
The no-frills shop has no electricity, but the neighbour had been donating power so Cheep Shop staff could have an electric jug operating as well as one light.
"For a joke we've got the customer torch ... it's just a way of acknowledging to the customers we have no overheads."
There were three to four regular volunteers who worked at the shop but none wanted to take on the manager's job or work the till.
The manager's job involved about nine hours work a week, five of those at the store during its opening hours on a Saturday with a bit of weekday work to organise donated goods.
She also managed the till on Saturdays and priced goods to be sold.
If the Cheep Shop found a new site that got more foot traffic it may be able to open again and have a paid manager, Grant said.
Grant has joined the Wanganui Model and Miniature Club and will now put her attention towards a project creating a model of a Swedish cottage.