I can only see 1 review rated at 2 stars and somehow TripAdvisor is showing 4 stars!!! Very similar experience. Was on the road from Medan via Berastagi and Ketambe and on to Banda. A bad fall in Ketambe meant I had six stiches so was really looking forward to staying here after 8 hours of winding roads in a minibus. The deal was that Renggali is the best place to stay in Takengon. Got there after dark and there was nothing much to write about... except for some of thw worst experiences of staying in a hotel.
First up, at about 250000 rupiah (rack rate 350K upwards), this is as expensive as it gets in the region and Takengon is a small town at best. No one spoke English, which is alright; I love it when we don't know languages... it's fun. But that was it.
The entire hotel was empty but they refused to give me a lower rate or accommodate in the reception building even though I had a really bad leg. With no option, I finally went to the standard rooms quite far (corridors open out to the lake). The first room was stinking, old, lights were too low to read a book, bathroom was dirty... you get the idea. So I had to send them off to get some more keys.
Four rooms later, I selected one that didn't stink as much and felt relatively clear. Must have spent an hour trying to do this. Asked for clean towels, toilet paper, blankets, ... phew!
Midway through, the lights went out. So, well, no hot water or any water, for that matter, since the pump won't run.
That's not it. They don't have a kitchen for lunch or dinner. Your only option is to get a becak and ride to town. The becak costs 40,000 rupiah (20000 if you can haggle well). So, really, the cost for a room here is more like 400,000. Breakfast is served though ;-D
In the morning, just when I was about to brush, the electricity went out. It didn't come back till my minibus arrived, so no bath at all. Luckily, they had a water dispenser. So much for being the best hotel in Takengon.
Fortunately, I had not paid in full so I refused to pay, wrote a big complaint letter and left.
The view is amazing though ;-D
My two cents... stay in town. Any of the hotels in the regions are infinitely better even at a fraction of the price. You can come over to the lake in a becak or walk over from town.