I have been looking at this recently and can confirm what i have been told
R22 Hull value £20,000.00
Allow £40 per hour
So machine with 1000 hour left 40 x 1000 = £40k + £20K hull = £60k
R44 Hull Value £38,000.00
Allow £60 per hour
this is basically what a dealer with give you for the aircraft if your buying you will need to add a bit