GREP multiple lines that are not next to each other

I have a text file that looks like this:

landlord: John Smith
  has:
    house: 0
    flat: 5
  available: 1
  cheap: 0
  quality: 1
landlord: Will Hall
  has:
    house: 3
    flat: 4
  available: 1
  cheap: 1
  quality: 0
landlord: Marry Moe
  has:
    house: 0
    flat: 2
  available: 1
  cheap: 1
  quality: 0

All I am interested in is landlord and available lines. How to grep the available: 1 line by landlord ? I mean cat filename | grep -i 'landlord: John Smith' and then check if available is 1 or 0 ?

Here is one way to do it:

egrep "(landlord|available)" filename | grep -A1 "John Smith"

UPD to check availability:

egrep "(landlord|available)" filename | grep -A1 "John Smith" | grep -c "available: 1"

You can use this command for the same:

grep -A 4 -i 'John Smith' test.txt | grep -i available