So i got a good deal on fencing 350$, decided to incorporate pebbles and grass . the space is about 30 by 15 ft. Re using Plants while incorporating more , trying to have water feature with 10 by 10 pergola feature provided by owner. But how can i add heights to the yard with water and building feature ? should I have retain walls ? because the hill gradually slopes to add a level effect. I would say i get off lucky on this project so far, weird budget and proposal.