Multiple DHCP on the same Router: OK - but networks???

Hello
I would like to put on a central DHCP for different vlans.

The diagram is the following:

eth1: WAN
eth2: trunk port with multiple VLAN

vlan 501: network #1
vlan 502: network #2
the same can be achieved with multiple phisical interfaces.


VLAN 501:
router ip: 192.168.1.254 - /24 subnet.
I configure network parameters in dhcp config and everything works.

What happens if VLAN 502 has the same subnet but different parameters?
I can’t do that.

for example: vlan 502 using a different ntp server or different gw (example if vlan 502 router ip is 192.168.1.0/24 ?)

how can i do that?

thank you