Host Unable to Communicate with Guest

[xeu100]

As the title says, my guest works fine and works with the internet, but the host cannot use any ports inside of the guest (such as LDAP or SSH). My goal would be to allow guest to continue accessing the network without individually portforwarding ports I need while also having guest<->host communication.

NOTE: vmbr1 is an unrelated bridge for internal VMs, everything is running on vmbr0.

Here's my /etc/network/interfaces (HOST):

auto lo
iface lo inet loopback

iface eno3 inet manual

iface eno4 inet manual

auto vmbr0
iface vmbr0 inet static
        address 144.[abc123].197/24
        gateway 144.[abc123].254
        bridge-ports eno3
        bridge-stp off
        bridge-fd 0
        hwaddress 0C:C4:7A:94:4A:86

iface vmbr0 inet static
        address 144.[abc456].140/30
        gateway 144.[abc456].254

iface vmbr0 inet6 static
        address 2607:[xyz123]::/64
        gateway 2607:[xyz123]:FF

auto vmbr1
iface vmbr1 inet static
        address 192.168.50.1
        netmask 255.255.255.0
        bridge-ports none
        bridge-stp off
        bridge-fd 0
        post-up echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up   iptables -t nat -A POSTROUTING -s '192.168.50.0/24' -o vmbr0 -j MASQUERADE
        post-down iptables -t nat -D POSTROUTING -s '192.168.50.0/24' -o vmbr0 -j MASQUERADE

/etc/network/interfaces (GUEST)

source /etc/network/interfaces.d/*

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto ens18
iface ens18 inet static
        address 144.[abc456].140/30
        gateway 144.[abc456].254
        # dns-* options are implemented by the resolvconf package, if installed
        dns-nameservers 144.[abc456].254 1.1.1.1 1.0.0.1
        dns-search [an]

iface ens18 inet6 static
        address 2607:[xyz123]::
        netmask 64
        #gateway 2607:[xyz123]:FF
        pre-up  echo 0 > /proc/sys/net/ipv6/conf/ens18/accept_dad