If you make your own boards, then it's likely you be doing more then one. I think it something you will need to figure out on your own. A drill press is a very good investment, even if you only do a few projects a year, and can be used for other things. I, like most people made do with what we had on hand. A regular drill or dremel will get the job done, but its kind of slow going, break a lot of bits.
When I started using more ICs, and more recently microcontrollers, need to do more precise drilling, and had more holes per board. I bought an 8" benchtop from Big Lots around $40. It's fast enough for carbide bits, much quieter, less vibration. Wish I'd done it years ago. Do maybe 1-3 boards a month, not high volume, and still using the same bit about 3 months now...