Like others have said, see if you can decrease your 401k contribution but just enough to get the employee match. This won’t be a lot but it is something. Can your fiancé help? I think joint accounts is best if you feel this will be a long term gig (Kind of like combining powers).

I would not sacrifice the flexibility and your job might pay you more in a few years.

Side note: I started to sell stock options this year kind of as a side hustle (there is a learning curve but I think it went well). Our household is similar, we max our retirement and with expenses it’s hard to have “extra” that can go to other things (without decreasing amount going into retirement). This is what motivated me to try and find a side hustle.

Good rule of thumb is, nothing is ever easy. If it seems too easy there is a catch somewhere. After all if it was easy then everyone would do it and everyone would make it. (Recommend more solid blue chip stocks, MSFT, HD, CVX)