As a startup founder that's not VC funded, I would totally recommend you look into building with kubernetes from the get go. The biggest learning curve is for the person setting up the initial deployments, services, ingress etc Most other team members may just need to maybe change the image name and kubectl apply to roll things out. Knowing that rollouts won't bring down prod and that they can be tested in different environments consistently is really valuable.

I started out with Iaas namely Google App Engine and we suffered a ton with huge bills especially from our managed db instance. Once the costs were too high we moved to VMs. Doing deployments was fine but complicated enough that only seasoned team members could do it safely. We needed to build a lot of checks, monitoring etc to do this safely. A bunch of random scripts existed to set things up and migrating base operating system etc required a ton of time. Moving to kubernetes was a breath of fresh air and I wish we'd done it earlier. We now have an easy repeatable process . Infra is easier to understand. Rollouts are safer and honestly, the system is safer too. We know exactly what ports can allow ingress, what service boundaries exist. What cronjobs are configured, their state etc with simple kubectl commands.

Using kubernetes forces you to write configurable code and is very similar to testing: it sounds like it'll slow you down and shouldn't be invested in until the codebase is at a certain size but we've all learned from experience how is actually speeds everything up, makes larger changes faster, cheaper customer support and saves you from explaining why a certain feature has been broken for 10 without anyone's knowledge