I already built an MVP I built the MSI installer to package my python code together with my freelance developer. However, the installer is kinda buggy and it doesn't seem a good use of time if we have to learn how to build a proper installer ourselves. If I post a job on UpWork however, I am not ...

Before launch, to find bugs or validate wording. Have you tried www.betabound.com or other communities? The first customers could be difficult to acquire. Do you think they should be beta testers?