We had a great time at William's home. I will divide my comments in topics and people can search as they wish.

House
The bedroom is very clean, the bed is comfortable, the air conditioning works fine and the private bathroom has an excellent shower.
We received a key and we could come and go always accordingly with our convenience.
They have two sweet and quiet cats and even myself that don't enjoy pets liked them.

Location
It is in East Harlem, we could walk safely during the day and we went there in June, so the day lasted until 08:30 pm.
The subway station is between 7 and 10 minutes walking.
At very late night, we don't know because we took a taxi.
We spent around 30 minutes between house and Times Square.
I landed on JFK, we got there by metro (air train to Jamaica /line E to 51st/line 4 to 110 st), it is a little bit tiring after a long trip and at last day we came back by taxi.

Some transportation costs
Metrocard for one week US$ 32,00
Uber taxi from house to Penn Station US$ 19,25 at 03:15 am on weekday.
Regular taxi from Penn Station to house US$ 21,80 at 01:00 am on weekday.
Uber taxi from house to JFK US$ 58,72 at 05:00 pm on weekday.

Hosts
They were great hosts available for help you or respect your space.
We had some pleasant conversations not every day because we were always very tired when we got home. I think that we've made friends.

Regards,
CS