I'll just start with the last bit with a nit pick
. You wouldn't measure the speakers particularly but the response at given points in the room (depending on your needs). Measuring speakers you're making is a bit different. If the guy wanted to experiment or not would be a personal choice, just like you choosing to put together speakers from odds and ends for fun. Personally I'd be curious if it could be improved upon by improving response, whether it was simply a matter of finding a better spot for the speakers or the seat, or (horrors) applying a bit of eq. Or not. Some guys buy ridiculously expensive cables to try and tweak the sound without trying science
YMMV.
As to measuring gear for speaker making, a DATS kit from Parts-Express could help identify T/S parameters if you didn't have those among other things for speaker design/measurement. They bundle it with their Omnimic kit (measuring mic, software package) for room measurement....but for room measurement you could buy a measurement mic and use REW software for less $.