Thanks, @allio, for the link to the 10-port switch; if they went with that, they could possibly get away with a 16 port standard switch (so 26 total, 8 being PoE+) - I’ll need them to count all the cables coming into the garage to make sure they’re covered (plus allowance for devices like the NAS), but it could be safer to still go with a 24 plus the 10 (only $60-70 difference between the 16 and 24).
Noting the electricians still haven’t put in a patch panel, can I also get advice on the best approach - are they best to get them to use one that has the cables punched down,as opposed to having them put plugs on all cables and using two-way joiners? If punched down, is this a suitable product (assuming 24 ports is adequate)? https://www.pbtech.co.nz/product/CHSDNX1058/Dynamix-PP-C6S-24-24-Port-Cat6-Shielded-Patch-Pane
Just remember to account for the fact that you lose a port on each switch for uplink. And one of the ports on the 10 port TP-Link is SFP, not standard ethernet. Makes for a great uplink port with a DAC but the other switch has no SFP so you'd need an SFP -> ethernet adapter to make use of it. I would go with the 24 plus the 10. Just remember to keep comparing against the cost of a 24 port PoE switch (around $500) to make sure the two-switch decision actually makes sense.
Not sure if the second hand route appeals to you at all but there are oodles of 24 port PoE switches in the $100-200 range on Trademe.
You definitely want a patch panel, not cable jacks. The one you linked is the same one I have and it works great.