Two Mikrotik redundancy/failover

Hi All!

Sorry for the long post, TLDR:
Can I somehow make some backup/failover solution using TWO Mikrotik routers, capable of serving the same subnets when one of the devices fails? So not a 2 WAN failover on a single device, essentially a single WAN on 2 devices, but I'd need redundant gateway, DHCP, VPN connections. Their WAN gateway has multiple ports, I could set up VPN on both, but I have no idea at the moment how could be the two routers both be a possible (default) gateway for the subnets.

The long story:
I am helping with a small company with their networking when they need support, mostly remotely, but last time needed on-site work as their Mikrotik's PSU has failed which provides me the remote access through OpenVPN. The problem is that I am moving farther away, so on-site repairs will be a no-go for me, but it is hard to find people with advanced networking knowledge in the small town, capable of more than plugging in ethernet cables.

The single point of failure WAN is a non-issue, it's ISP equipment and if they call them, they fix it reasonably quickly, but they won't touch the Miktorik. If their single switch fails, someone with ethernet plugging skills can replace that too, and their server already have redundant eth ports.

So. Even though I fixed their device yesterday, I could now convince them to buy new ones, even two, to make the most cruical part of their network redundant.

I can configure the VPN so I can access both devices, might be able to configure the two routers to both act as a their DHCP server, and I could reconfigure things manually (the default gw specifically) should one of the devices are not working properly, but I'd like to hear suggestions how could I improve this to minimize the human interventions needed.