OK, so German houses. Round here they seem to be of three types. The first look exactly like a child's drawing of a house - sloped roof, 4 windows, except the door is often around the side. I think they are really ugly and blocky but almost every house looks like this. They are deeper than they are wide, and they are often divided, either into two houses side by side (so, semi-detached) or with one stairwell and then 3-4 flats one for each storey. They don't always have a balcony here, that's more usual on the side that doesn't face the street anyway.
Or you get flats lining streets in urban areas, about 3-4 stories high, sometimes with shops on the ground floor in town centres but just houses all the way to the ground in residential streets. These range from concrete block to elaborate Gothic designs, really interesting.
Then there are the "Alpine" type houses with loads of dark wood and huge balconies and rooves that look like something out of Heidi. I love these houses! I couldn't find a really good picture but I couldn't be bothered to keep searching the estate agent websites.
There are also modern new builds, but these are usually in newly-developed areas, lots of modern looking flats, and boring concrete box type high rises but these are few and far between. Possibly they have more in inner city areas but I only live in a small city.
Common features of German houses/differences to UK:
Flats tend to be really spacious and not at all considered lesser to houses. If there's any kind of "level" at all, it's for an "Einfamilienhaus" (one family house) over a "Mehrfamilienhaus" or "Doppelhaus" - ie, a detached house rather than a flat or semi-detached. But it's not taken that seriously and nobody would look down on you for not having a detached house, it's just sort of seen as more desirable to have one. Granny annexes are really common, and lots of people rent them out to students while their parents are young, and only when their parents get really old and frail, or one dies, will they move them in there.
There is no "housing ladder" as such. There are huge financial penalties if you sell a house within 10 years of buying it, so unless you plan to live somewhere more than 10 years, it's not financially viable to buy at all. Most people first buy when they have a youngish family, or (if they're very lucky) before starting a family, and stay in the same house until they become too old and frail. At which point they move to an old people's home (which are lovely) or to live in a child's Granny annexe. It's not common for people to move every few years or start with a smaller house and trade up. Rights for tenants are extremely good, to the point that you can't evict someone if you're selling up, so you can buy a house with sitting tenants in, something that often catches out foreigners! As people live in the same house for 30, 40, 50+ years, it's common to buy a plot of land and build a house, or buy an outdated husk that needs completely gutting and redoing. It would be very rare to move into a house that is totally ready to live in. Old houses ("Altbau") are desirable if you like that sort of thing, although can be more complicated to renovate.
Even for renting, people generally take fittings such as the light fittings, curtain rails, and the entire fitted kitchen with them to their new flat. I find this absolutely bonkers (surely the cabinets don't fit?) apparently it's because kitchens are considered very personal and might have absorbed cooking smells 
about 30-40% of the time, the previous tenant will want to leave the kitchen in situ, but they then have to persuade the new tenant to buy the kitchen off them, for whatever price they deem reasonable. If the new tenant refuses, the old tenant has to dispose of the kitchen before they leave. You often see kitchens for sale (including the sink, counters, extractor fan etc) on ebay Kleinanzeigen or Facebook marketplace. Light fittings aren't always wired up correctly - in our current flat, the cable in earth colours is live and I think the brown one acts as earth, so somebody made a mistake. Unlike the UK, when the flat part pointing up always means on, there is no consistency in lightswitches, they can be either way up, so it can be a bit hazardous trying to fit light fittings when you first move in and can't tell whether the light is switched on or not.
Metal shutters (Rolladen) are extremely common. We have them on one side of our building but not the other side. Many people these days have automatic/electric ones but ours are just controlled using tapes/cords. They are very useful for keeping the sun out during hot summers which prevents the house from getting too hot. As a consequence it's hard to buy curtains which actually block light, most curtains here are really thin and a lot are actually just gauze, like you'd think of as net curtains in the UK. I bought our light-blocking curtains from Ikea but it's hard to find them, and expensive, and you can't buy curtain liners - I'd have to probably find someone who can sew and get them made up.
Another thing it's hard to find is double sized mattresses and duvets and duvet sets. People here typically have a single mattress each which they put side by side on a 180x200 bed frame. This is because it's considered very important to have the correct "Lattenrost" which is basically the slats that go under the mattress. Imagine our surprise when we bought beds here, to discover they don't come with anything to support the mattress - no slats at all. Just an empty bed frame. What you are supposed to do is buy these Lattenrost, which have no name in English, these are sturdy contraptions that slot into the bed under where the mattress goes in order to lay your mattress on. They have various combinations of sprung bits, tensioned wood, plastic torture devices, head raising parts etc and cost an eye watering amount of money. So most people buy an individual one for each person in the couple in order to get the best type, and then you purchase your mattress according to the softness already provided by the Lattenrost and your own comfort level. Which means 2x single mattresses. You can then buy a little bridge to put in the middle, if the gap bothers you. And most people use a king sized sheet over the top, but then have two separate duvets with two separate duvet covers. Again I just buy all of ours from Ikea, because I can't be arsed with the whole separate thing.
There is often a plug socket directly below the light switch, especially in older buildings without a lot of sockets. This is to plug the hoover into. Electric sockets are normal in the bathroom, and our lightswitches are inside the bathrooms, but there are good electrical safety codes so anything unless it's really out of date will have an extremely fast tripping switch for the bathroom, which is supposed to prevent any accidental electrocution due to water contamination. I think we might be overcautious about this in the UK. I remember my physics teacher saying that if we turned on a light switch with wet hands, the current would jump through the plastic to our wet skin. It has never happened to anyone I've heard of. Maybe English lightswitches are particularly thin.
Fitted carpets are really rare - sometimes you find them in bedrooms. Never in main rooms of the house, it's considered dirty. And nobody wears their shoes in the house, not even visitors, tradesmen tend to, if they're doing something messy. They get even more squeamish about shoes on beds. When I was in hospital having DS2, I had to bring flip flops to wear so that my bare feet could not touch both the floor and bed, as this would be contaminating.
Balconies are fairly common, even in normal houses but definitely in flats. Most flats also have a storage space in the cellar for each house, and a laundry room in the cellar is common as well. We have a bike room in ours instead. Lifts can seem quite outdated - I was nervous of ours at first, as the outer door isn't automatic, it is an actual heavy door that you pull or push open. But the inside of the lift is fine, and I'm used to it now. Some are really tiny, you couldn't fit a wheelchair inside and some are on alternate half-floors with the houses, which makes me wonder who they were originally designed for. It's also common in multi-family houses, whether that's a block of flats or a 3-4 storey child's drawing house, for one of the flats to be a doctor's surgery, dental surgery or some kind of therapy practice. So when you go along to the doctor it's often just an ordinary flat from the outside until you go in through the door, I always find this really bizarre! And living with that dentist smell in the corridors would make me so nervous :o On the plus side, IME noise proofing is often done incredibly well and you aren't bothered by your neighbours. It's common to have communal outdoor drying space, space for children to play as well.