Well I think we should welcome forum members from all over the globe and try to help them with advice that is common to gardens anywhere. If the poster decides that they need more localised advice that's up to them.
If the soil was as bad as you described, I think your yard should have been rotovated before the much was laid as most new plants, bulbs etc. will struggle to get their roots down into a rock hard soil.
I understand you want to make your property as attractive as possible to sell it but I hope you have not wasted your money, time and effort as there is no guarantee the new owners of your condo will want a garden and just remove everything you have done and cover it with concrete or similar.
When I sold my house to a couple they drooled over the garden, unusual plants etc. etc. What a lovely garden da di da di da, grow our own veg. blah blah blah. It was what made them buy the house. I visited my neighbour a couple of years later to see the whole of my garden denuded, a huge concrete koi pond built and a few lollipop standard roses. It was a mistake to go back and see it, I had to remind myself it was no longer my garden, that I had a new garden to develop and everyone is entitled to do what they choose in their own garden. But it hurt to think of the plants gone to plant heaven before their allotted time.