We had a fantastic stay in Lilian's apartment. It really has everything you need for a stay in New York - it's located on a quiet street on a nice residential road in Harlem and close to the local subways (one is a 5 minute walk which takes you right into the centre) and there is another around 12 minutes away which also goes through the centre and down towards Brooklyn. It is also just a few minutes from a big whole foods store if you want to pick up anything on your way out.
Lilian as a host was extremely helpful - we were able to check in early and she even printed some tickets off for us that had been sent to us by email too late to do so in London.
We would thoroughly recommend Lilian and her flat and had a great stay. Thanks!
P.S. a handy thing we discovered is that an uber pool trip from most central spots only costs about $10, which is very useful if it's late and you don't fancy getting the subway back.