https://www.ribretubes.co.uk/gallery
Personally i am not sure the word investment is a good choice imo , i think retubing a boat is just a way of enjoying the confort of what you already have with maybe sound engine ,trailer etc , ,as far as the value goes ,the same people have been trying to sell a complete refurbed hull and tubes for a little while ,a 6.2 and their sister company xs have a 5.3 refurb for sale i think ,both look ed very reasonable on price but seem to have been for sale a long time !