Why are people against charging a smaller engine? Maybe he does not want to go through the effort of an engine swap, or very content with the car as is, but still wants a bit more umph. Bit like my 1.2 Micra which is supercharged (factory) - its not the quickest car in the world, but the boost make it much more fun drive compared to the NA motor!
Fitting a turbo is "fairly straight forward" affair if you are fairly hands on, essentially you will need an turbo manifold (may need to get one made up from scratch though...), then the down pipe to the rest of the exhaust.... then there is the intake plumbing with intercooler, as well as an oil feed + return (usually from oil filter with an adapter, when a return to the sump)...
The trick is to get the fuelling right. Low boost setups can usually get away with standard ECU with either a piggy back or a chip and that's it.
Start to increase the boost past "low boost" and you start maxing out things like injectors, fuel pumps to the cost starts to increase quite rapidly. High boost you may need to decrease the compression ratio, cams more suited to boosted engine.
As to what is considered "low boost" on these engines I'm not quite sure. I have 7psi stuck in my head but that's back from the SR20 days!