Just back from a very enjoyable stay in Carlos' apartment in Madrid.
Carlos was a perfect host, he allowed me to check in earlier than advertised owing to my early flight. This was a really big help and I appreciated it. He stayed in touch with a couple of messages to make sure everything was ok without being intrusive and he even left some food in the fridge! He really couldn't have been better.
The apartment is small, just one room, but the location is excellent. I'd go straight back to stay again.
A couple of things to note: there's no washing machine so be aware of that if you're planning a stay more than a few days. The bed is a sofa bed, which is absolutely not a problem but, if like me your Spanish isn't great or, like me, you weren't paying close attention to the add, you may not have noticed (me being dumb) Lastly the Wi-Fi isn't great. It's there but it drops in and out and, for me, wasn't always available on the couch/bed.
All in all, if you want a really well located, clean, functional base with a friendly and helpful host then I recommend you book this apartment