The former Irish Naval vessel Aisling, which was sold at auction two months ago for €110,000, is being offered for sale in Holland as a fisheries patrol vessel for $750,000 (€685,000).
The Permanent Defence Forces' Representative Association has said the sale of the vessel appears to have been a terrible deal.
PDFORRA, which represents sailors in the Naval Service, said it cannot understand why a higher reserve was not set.
The LÉ Aisling spent 36 years in service before it was decommissioned in June 2016 and sold at auction earlier this year.
There were only two bids for the LÉ Aisling when the vessel was auctioned at the Carrigaline Court Hotel in Cork in March.
It was bought by a Dutch ship broker, Dick van der Kamp, who said he planned to resell it on the international market.He described the purchase as a gamble.
In a statement Mr Van der Kamp's company said they "have marketed the vessel without a price" to see "what comes up."
The statement to RTÉ News added that the company "were not so happy that all over the internet the purchase price was advertised as this is giving a wrong impression about the value of the ship as such, but that value still has to be seen and that is what we are trying test right now".
Auctioneer Dominic Daly who sold the LÉ Aisling on behalf of the Department of Defence, and also sold the LÉ Emer and the LÉ Deirdre for substantially more money, said significant costs would have been involved in preparing the LÉ Aisling for re-sale.
Mr Daly said the cost of towing the ship to Holland and re-classifying the vessel could have run to hundreds of thousands of euro.
He explained that naval vessels are sold without classification and have to be re-classified before they can go back into service.
The LÉ Emer sold at auction for €320,000 four years ago, while the LÉ Deirdre sold for €240,000 in 2001.
