Yarrow is a great choice (tough, drought tolerant, and usually left alone). Other solid options that tend to hold up well with deer: lavender, salvia, catmint (nepeta), Russian sage, ornamental grasses (like little bluestem), and bulbs like daffodils/alliums.
For cost, it really depends on how “finished” you want it:
DIY refresh: $300–$1,500 (mulch + plants)
Pro install: $5k–$15k+ if there’s hardscape or irrigation involved
Big tip: keep it simple and repeat 4–6 plants in groups/drifts it looks cleaner and is easier to maintain (and deer don’t wipe everything out at once). https://app.neighborbrite.com/s/U4NSUgostxt
