I regret that my place could not comply with your demands. Yes indeed, there are road constructions at present in the neighbourhood, which I am sorry for, but which I cannot stop. The wify problem at Vogelsang was mentioned in the description, so you had been warned. But apparently, you did not talk to my housekeeper about that problem; she may have rebooted the wify router and helped you.
What is not true at all is your idea that the drinks could be overpriced. If you want discounter prices for your drinks, then go to a discounter and buy them there. You will spend time and petrol to get there, which will sum up to much more than 2.50€ for 0.75 liters of local mineral water from a spring that is not known to be cheap. You will pay a much higher price at any train or gas station and far more in a restaurant. Also, in spite of what you sugges, there is service: the drinks are being bought and transported to the house for my guests and the glasses that they use are washed daily. So the prices for drinks in my place altogether are low rather than high – and if you were unwilling to pay them, you could have drunken our wonderful tab water - completely for free. Apart from that, there are loads of cafés and restaurants in the neighbouring villages on and off the lake, so there are many opportunities to get a coffee in the afternoon.
Let me remind you that you were staying in the guest rooms of a seminar house. My place is neither hostel nor a hotel. If you want hotel service, then go to a hotel and pay hotel prices. I feel largely misjudged by being blamed for all shortcomings of your holiday.