1.Does it have DHCP functionality?
2.How many IP addresses can it get out?
3.How many units can use Wi-Fi at the same time?
1. Yes.
2. Using a VLAN starting with, say, 192.168.128.0/24 provides 253 addresses on that network. You could have multiple VLANs.
3. I only have a GX20, but I think it would be suitable for up to 50 clients.
Suggested reading:
GX20 Data Sheet
Meraki Go Indoor WiFi Access Point - GR10 Datasheet
Meraki Go Outdoor WiFi Access Point - GR60 Datasheet
Thank you for giving me good advice!!