As others have stated, having access to paint/body facilities is a huge plus, however, just make sure that 'favors' or 'deals' don't cost you more than going somewhere else.

The little things really do add up, in terms of cost, but also on the visual impact/quality of the final build. Whether it is to look stock or not.

For example, you can have a flawless paint job. But if your original glass is scratched/chipped, the stainless isn't fully polished, door handles and emblems are worn & faded then it will really hurt the look.

Lastly, if the car is already running/driving/functional before you take it apart, this is a plus because you can determine what still works well and doesn't need to be rebuilt. e.g. heater core, blower motor, steering box etc.

If you're building a basket case or roller, then it only makes sense to put back new or rebuilt components. Personally, I have no interest in swapping out a steering box from a freshly detailed engine compartment and suspension..