My S used either his Zoom video/audio recorder, has also used a laptop using the zoom as the mic, and it worked fine for him. Keep in mind they aren’t expecting perfection and unless the recording it totally horrible they likely will hear what they are listening for just fine. I will add a recording studio and professional person doing the recording is easier on you, if you don’t feel comfortable with the DIY, then by all means go that route, but my experience with it both personally and through the network of music families I know is it isn’t required, especially now that DIY has so many options.
One warning, don’t try and make a bad recording sound better with things like reverb or playing with the waveform recording, one advantage of DYI is you can do takes until you are happy with it, and the only cost is time:).