I suggest you research cap expenses and cash flow on BP. I invest in San Diego county and unfortunately believe your property as described above is negative cash flow after including cap expense, vacancy, and maintenance.
Does this imply that it is a poor investment? Possibly not but you are relying on appreciation to do well on this investment. Fortunately San Diego has done well in the appreciation area.
I do have a little experience on having property in Germany but not enough to make a recommendation either for or against investing there. I no longer have property in Germany but my situation was different than your situation (i.e. I was not living in Germany).
If you invest in San Diego I suggest using a cap expense cost of $300/month for SFR. Allocate 10% for vacancy and maintenance. Finding a property that cash flows with these numbers in San Diego likely eliminates SFR and requires multiplexes. If you can handle some negative cash flow you can invest in SFR in San Diego in hopes of appreciation but if you are not in San Diego I question why San Diego.
I invest here because I live here and can manage the properties. I have done well investing here and am pro So Cal investing but if I did not live here I probably would invest elsewhere.
Good luck.