Moving to Germany but have 2 options

I’m in the process of moving to Germany temporarily on a 1 year working holiday visa. I can either apply within Germany, or in Toronto before going to Germany, but there are pros and cons to both:

Within Germany
I luckily came across a slot that freed up at the immigration office on September 22nd, however this is very soon and I need to get my living situation sorted before then to register my address. I got a place lined up thanks to my German boyfriend, but rent is a bit steep for the location. Since I won’t be able to work until my visa is processed, I am going to be paying this rent indefinitely without income. But the people are very lovely and are willing to get documents sorted in a timely manner so they’re ready for my appointments.

This also needs to happen on a quick timeline because i have been in Germany a significant amount in the last 180 days, so I only have 24 days remaining in Germany visa free. I can’t just go knowing I have 3 months to find an appointment at the immigration office.

In Canada
Flying out to Toronto would be an additional cost I have to consider, however this way I’m able to go into Germany and stay with my boyfriend for next to no cost until I find an apartment. I can’t get a job until I register an address with the city, but at least I’m not paying large sums in rent.

My dilemma stems from how much trouble it might be to find an apartment (or sublease) willing to get the signature and permissions i need from their landlord. I’ve heard a lot of subleases are done without the landlord’s knowledge and it can be hard to get the necessary documents to properly register as a citizen. I am also not currently a student since I’m taking a gap year, so I’m worried this will also limit my options.

Based on what I’ve said here, what should I do? Please let me know if you’d like more details !