All of my models are custom built in my workshop. Most details were mastered, molded and cast here, but are now quickly being replaced by 3D printed models, with far superior precision and freedom to model the empty spaces. And less cost in the long run, as the 3D printer builds the assemblies rather than I painstaking gluing small 2D parts together.
I never like to build two models of the same ship the identical way, with the same colors and details. I like to vary the rigs and details from ship to ship, as they vary in real life, even on consecutive models from the same production line. I do this so that everyone gets a ship that is at least a little different from others. The variations keep the ships fresh. There is always equivalent detail compared to the published model and usually more.
The same goes for paint schemes and names. You can change names and colors if you’d like to–I usually encourage it, in fact. Like details, colors, names and home ports add variety. Below is an example of four of my fishing vessels with varying details and color schemes from the first versions.

Of course there are times when absolute fidelity to history is of utmost importance. A model of the Indianapolis heavy cruiser on her final mission must be faithful to every detail—no freelancing allowed here. Warships are usually very well documented. While they were updated regularly, it is usually but not always possible to find photos of every important update. Some US Navy and Coast Guard ships served for 60+ years, so there are always variations to model.
A good example is the 215’ Reliance USCG cutters, which started life without stacks for more helicopter landing area. The horizontal exhaust was difficult to maintain and robbed interior space, so the USCG modified the ships in the mid 1980s for vertical stacks.
On the civilian side, the Port Welcome of Baltimore Harbor is the Port Welcome with subtle changes in details over the years—unless you want to put it in Boston Harbor and call her something else. Still, if you are modeling an era when the Port Welcome had Navy-stye davits instead of the later quadrants or scrapped the lifeboats for the canister-style life rafts, these changes are easily made, usually without charge.
Peter Nolan