Adrian's apartment is a great place to stay if you still want to be close to the city center but avoid the crazy costs. It's right next to the Clapham Northern Underground station and it's only 3 stops to London Victoria Station which puts you in the center of everything. But Clapham itself is a nice area to go out in and explore if dont feel like venturing to Central London for the nightlife.
The apartment had everything you needed, looked exactly as depicted in the pictures and Adrian provided clear instructions on the check in process.
Overall, I would stay at Adrian's place if I return to London