I'm looking at the Nokia 5 @ around €150 (euros)
amazon.de linkListed as
Nokia 5 Dual SIM Smartphone - deutsche Ware (13,2 cm (5,2"), 16GB, 13 Megapixel Kamera, Android 7.0)Apparently has been, or can be, updated to Android 8.
Has dual sim *plus* an sd card slot.
Amazon reviews generally positive -- although a lot of the one star reviews talk about it giving up after a month or two, which is a little worrying. Camera not so good (pity), although hard to know what people are comparing it to. (FWIW I have been very happy with the Nokia 730/735 phone camera -- not great in low light, but otherwise takes quite nice pics.)
I haven't done a lot of research -- am still using the Nokia 735, a windows phone, but, due to broken screen which costs more than above linked phone to replace, it's on the way out. Off-topic// Windows has been very limiting at times, but in general I loved it, and will miss it.
So if anyone has any opinion, or other suggestions in the lower price segment (under 200 euros or so), do say. If not, I will eventually get my act together, do some more research, and report back.