Duckydc’s list is great, but I agree that some sound a little on the low side.
For us, recurring costs include dog walking at $18/day x 3 days, plus daycare at $33/day x 2 days = $120 just on care while we’re at work during any given week.
High quality food is about $2 per day x 7 days a week = $14 per week, plus maybe $10 in treats.
We’ve spent a crazy amount on toys because she’s unexpectedly eaten through most of them – probably to the tune $150 so far.
Our vet bills in the first month (one intro exam and vaccine booster, plus an emergency trip after she seemed to choke on a chicken bone) have run to about $400 and her adoption fee was $325. We are working with a trainer who offers a discounted fee of $90 per session for adopted dogs and she has been invaluable so far (2 sessions = $180).
Her crate and other set-up stuff (crate, leash, bowls, collar, tags, harness, poo bags, heart worm meds, etc) was about $250 all told.
Our (probably still conservative) grand total for month one of dog adoption: $1,800!
Costs will definitely taper off and some costs you have more control over – we use Friendship as a vet for example, because we trust them based on previous experience, but there are cheaper practices out there, or we could downgrade her food, or opt not to use a dog walker – but it is definitely an endeavor! Good luck!