On made-to-measure, and why the price being close to good off-the-rack should indeed make you suspicious.
Made-to-measure usually means a standard block adjusted to your measurements, a real improvement if you are an unusual shape, and largely wasted if you are close to a standard size, because a tailor can achieve the same result on an off-the-rack suit for less. At the cheap end the adjustments are limited and the fabric and construction are where the money was saved, and you can end up with a worse garment that fits slightly better.
It starts making sense if you are hard to fit off the rack: long or short in the body, a big difference between chest and waist, sloping or uneven shoulders. Those are exactly the cases where alterations run into the "effectively impossible" list above.
For a first suit worn twice a year, I would spend the extra on fabric and a tailor rather than on measurement. Practical version: mid-grey or navy, plain, wool, nothing shiny, and a weight you can wear in more than one season. That suit works for a wedding, an interview and a funeral, which is exactly the life you described. Avoid black - it is the one people buy first and the one that only really works for funerals.