I was recently asked to "ride" and "oily rag" bike (non Douglas) that was having its first outing on a veteran rally. It did start and go, but other than that it was a disgraceful potential death trap.
I have a number of bikes that have original finish, and others that I haven't spent money on paint and plating. But underneath the mechanical essentials have been done. Please, please, please make sure that, at the very last, all the control cables, front fork and steering, brakes, and wheels (bearings, spokes, rims, tyres and tubes) have been thoroughly serviced (and renovated if necessary) and are in good working order. Even if you don't need an MOT, safety should be paramount.
Cheers
Leon