Difficult to provide any ideas without knowing the size (square footage), the aspect and the geographic location. That is just basic information necessary to respond to any landscape/garden design request.

To my eye it looks like you have space for a bbq perpendicular to the AC unit, a table and chairs perpendicular to the slider, and a few pots for plants and that’s it

I would start by fencing the AC unit with a plain horizontal fencing (not lattice) Next to the utility I would add tall decorative grasses either planted in ground or in a container. I would use this space for relaxing Add a couch /sectional a coffee table with storage (for pillows) .

Start by having the brick patio pressure washed. It will look fresh and new again.

Will you need seating for two or four? Bring out some folding chairs and a card table if you have them to see how much space is taken up. You could have room for a 36 or 48 inch round table or a couple chairs with small table in between. A small electric grill would probably fit quite nicely.

Some ideas

We need to know the size of the space and that would aslo be the space for the AC , how mant seats the size of the BBQ. Too much missing info

Before buying anything, check with the HOA to see what the rules are. CHances are good they are designed to keep the neighbors' relationships smooth. You cannot block access to the electric meters but you may be able to install a gate. Check to see if barbecues and fire pits are permitted there.