So many grays turn blue. after much trial and error for bdrm, bath and water closet , i'm happy with Benjamin Moore Horizon and Behr ultra in Burnished Clay. Neither look great on the card but they dry to a soft neutral gray. worth getting samples to try.

Do they have to be paint buckets? I would think they would not be good for gardening? Maybe others will know more about that. But in the U.S. you can get 5 gallon buckets from some local businesses like bakeries, food store chains, places like those that regularly use items they get in the buckets. For instance a bakery usually gets stuff in 5 gallon buckets and often has to throw them into a dumpster as they can only save so many. Some businesses now sell them for a small fee, maybe 1 dollar U.S. each and some just give them away. I think the cost of shipping them to India would be more than the cost of buying them. You could try setting up a fund on Kiva.org and possibly get enough donations to purchase food grade buckets instead of using ones from paint. Good luck with this project and please update us as to your progress.

Greetings From Dream Design, As per your Requirements we are suggestion you some changes -White color -where It is Grey -Dark Cream -Where Blue as it will highlight that area and also well goes with Bricks -and Trims take Dark cream -For Shutters you can also use Cream color So use the White and dark cream with combination as brick part is already dark If you need more help Pls mail us. Thanks Dream Design

you can try to get precast ferrocement slabs with required size and place it , which is economical, orelse use a meal frame