Everything was good. Abu is super gentle in messages and flexible on helping with check in. Our flight was very delayed and we managed to get to the apartment up on night. However we were able to get in the flat with the locker and detailed instructions from Abu.
Flat is great, with a great view and in quiet district, in walk distance from historical center. Of course you should be aware about Lisbon itself, it's kinda hills :)
And about Abu's place, we found only one difficulty - stairs with no elevator. For young healthy people this will not be a problem, but if you're traveling with a kid as we and especially with the baby carriage, this will be a challenge.
Anyway we enjoyed staying in the Abu's place and wish him all the best.