Similar strategies here. DH has quite severe ADHD, I would say. If something isn't in his routine, it just doesn't happen, even if he was reminded about it an hour before. Once it's in his routine, it's reliable.
For work, he has alarms set for every task he does each day. He's a school site manager, so he has alarms for distributing fruit to classrooms, opening gates for children, legionella testing, fire alarm checks, etc., etc. If he forgets his phone in the morning, his day goes a bit haywire.
He also splinters, so things that he's great at in work (such as fire marshall) completely dissolve at home, so I have to say 'how would we get out in a fire?' if he's moved furniture for DIY. You'd think they're the same, but it's different.
I don't think you can mask ADHD in the same way as ASD, but you can compensate so much that other people don't see it. I have ADHD (medicated), but if you asked people about me they'd say I am 'scarily organised'. I have to be. I have 3 teen children with SN and a husband who has ADHD who can't compensate as well as me. My diary is on my phone (shared with my DH and my parents), I have reminders set and I check it religiously.
Budgeting - we use YNAB. Both of us can see the budget. It's live, and it has a widget on our phones so you we update spending to it immediately. It's a rule that YNAB is updated at the till for DH. I run the budget, so I can be a bit more flexible.
Whatever appointment I have, I add 30 minutes so that I'm not rushing in the car and I never have the last minute panic of running late because that makes me a worse driver.
I do still hyper focus. At the moment it's decorating, so I'm awake and pinging at 05.00 and decorating by 05.30, before the girls get up at 7.30. it's annoying because I'm exhausted, but I have to forgive myself because it's not going to change.
I still drop the ball sometimes. Ironically, I double booked the girls' dentist appointments with my ADHD medication follow up, so I'm having to wait until March to get it increased.
Anyway, if you do want an assessment quicker, ADHD UK have a list of the current right to choose waiting times. I'm pretty sure that HealthHarmonie Minds is the provider with the shortest wait time, no separate waiting list for meds, and will prescribe even if your GP surgery refuse shared care. They've been very good so far with my DD1. I asked for referral 2 weeks ago. She has had the triage forms, which I completed. It rightly flagged mental health concerns, so they have sent me a further link to give details of her mental health care. They seem responsible.