Labour of Love

[Airframes]

Difficult to say - there are some kits at 1/48th scale that are in excess of £500 (approx $750), as limited-run releases.
A mass-produced, 1/32nd scale Spitfire or P-51, by Tamiya costs around £125 or more in the UK. Retail price depends on many variables - the target 'audience', popularity, and hence 'saleability' of the subject, the subject itself, complexity of parts etc. And of course, there is a limit to what can be achieved, in scale, the larger the subject and scale of subject, before the physical size affects the 'rigidity' of the finished model, not to mention the enormous cost of producing the moulding tool in the first place.( a cost that, even for a 1/72nd scale kit, is frightening!)
Those 1:1 'models' produced by Gate Guardians are mainly GRP and similar, over a steel skeleton, otherwise they'd collapse under their own weight, or, for example, end up with 'floppy' wings.

 

[Milosh]

Supermarine Spitfire Mk VIII 1/32 Tamiya MSRP: $189.00

A6M5 Model 52 Zeke Zero Fighter 1/32 Tamiya MSRP: $163.00

and the cost increase is not linear.

 

[tyrodtom]

There's some 1/16th models of WW1 aircraft at Historic Aviation, Fokker triplane, Nieuport, etc., you can build them less outer covering so the structure shows, up to $450.

 

[Airframes]

And if you check a certain other Japanese manufacturer, you'll see that their prices are nothing short of banditry on some of their kits - especially 40+ year old, inaccurate, basic (by today's standards) kits, re-issued time and again, with perhaps different decals. Some of this particular company's 1/72nd scale, 'fighter sized' kits are in excess of £40 (approx $60) !!
But on the other hand, Revell AG can release 1/32nd scale 'bomber size' kits at prices ranging between £40 and £50 approx, which are exceptionally well detailed and produced.
So I guess that, at around £22,000 for a completely finished, painted and delivered, 1:1 Spitfire from Gate Guardians, as a 'weather proof' static exhibit, the price ain't at all bad. And, such 'models' have allowed quite a number of real 'Gate Guards' to be 'rescued' and restored, some to airworthiness.

 

[gumbyk]

In the James May program, they had to go away from the plastic, it just wasn't strong enough to support its own weight at that size.

 

[Airframes]

Yep - trying to maintain actual dimension and form was beyond the rigidity of the plastic gauge required. They ended up using moulded GRP, as in their 'proper' 1:1 products, but in order to try and stay reasonably close to the construction kit theme, altered the actual assembly and construction method. That 'model', built by the local school children, is now on display at the RAF Museum Cosford, shown here in this photo taken almost exactly at year ago.

 

[mhuxt]

That James May proggie was epic.

The trials and tribulations of the Spit builder put into even sharper relief the staggering accomplishment of Glyn Powell, who hand-built a flying Mosquito and all of the associated jigs and moulds. Utterly breathtaking.

 

[nuuumannn]

That 'model', built by the local school children, is now on display at the RAF Museum Cosford, shown here in this photo taken almost exactly at year ago.

Can't be based on an Airfix kit; it doesn't have raised panel lines a foot thick and rivets the size of a frying pan.

That guy has some skills.