Full-scale Model Vehicles and Scaled Down Vehicles

A scale model is often smaller than the real thing. Matchbox cars, Dinky toys, Tonka toys or whatever appear at a cursory glance to resemble real vehicles quite closely but clearly they lack engines, electrics and often even working doors, and are only partly made of the same materials. I suggest these models be scaled up to real vehicle size and placed in the likes of car parks, garages, roadsides among their real counterparts with arrangements in place with the appropriate bodies such as councils, traffic wardens, car park authorities and the like.

From a distance, these vehicles will look real. As one approaches them, however, it may or may not become clear that they are to some extent fake due to the likes of perspex/plexiglass windows, General Lee-type doors and plastic tyres, or on the other hand a casual passerby might not even notice. I probably wouldn't. It would be interesting to see how accurate or not the models are compared to the real versions, and add a surreal quality to everyday life. Moreover, to a very limited extent the models would be functional, because they might actually be mobile to some extent. Scaling them up, however, would probably also introduce problems such as weak axles, soft tyres and transparent plastic becoming translucent due to exposure to sunlight.

In the meantime, the vacancies created by scaling up the models could be filled by tiny functional scaled-down vehicles made of authentic parts and materials on a minute scale. I presume these would have to be either electric, hydrogen or LPG-powered, since I imagine either diesel or petrol would be too viscous to function. Such models must correspond to real such vehicles rather than liquid fuel vehicles with replaced parts.

I suspect that a fully-working scaled-down model of a vehicle would be more expensive than a full-size version and that a full-size version of a model would be cheaper than a real version.

They would of course be fully insured and taxed etc. I'm interested in the legal and safety situation with both versions.