Relocation to JP in 2025

Hello everyone, and thank you for reading my question post. 
I received a relocation offer from my company and would like to ask for the basics based on your experience and knowledge. 
About myself: I am in my mid-30s, married, and the father of a young toddler (3 years old).

The offer is conditioned for a minimum stay of 3 years, so it will be crucial for me to do the right "homework" and be prepared for "what to ask for" in my relocation package.

I would highly appreciate your help and support to add any points I did not cover in my post and suggest any highlights to mention for me to comment on in my negotiations (package).

Relocation Questions: 

1. Visa application timeline:

The current plan is to start working in January 2025.
When should the company start the application process? 
The company has to apply via the local Japanese embassy at my origin. It is located in Asia. (Not in Japan.)
The company will likely apply for the Highly Skilled Professional Visa. What is the minimum salary to be declared? What is the title's position?

2. Rent in Tokyo:

The office location is around Tokyo Station, so I would like to travel for not more than 30 minutes (door to door).

Which area will be recommended for me to live in as an expat and is not too expensive? Shinagawa station? Shibuya ? Ebisu ? Ginza ? Roppongi ? Azabujuban ? Hiroo ?
Any other areas you would recommend checking?
Flat size: min. 120 sq m, 3 bed rooms
What is the cost range? 
Do you have a recommended agency to approach? Any other "ways" of managing this part?

3. Child Education: How to Choose an International Kindergarten? We are looking for an international kindergarten that will educate in both English and Japanese.
What is the process, and how long does it take? 
Do I have to physically attend the kindergarten before starting the application?
Do you have any recommendations?
 
4. Tax Payment: There is a "ton" of information online, but I would like to ask for clear advice. 
My spouse will likely be a "housewife," hence I will be the only person in the family working in Japan.

5. Healthcare: the company will arrange the policy. I would like to ask for any recommendations of insurance companies that are popular with expats in Japan. 

6. Cost of living: car and any other utilities.
What should be considered beside the "running cost," such as petrol, tax registration, car parking, and maintenance?

7. Housemaid: We would like to relocate our housemaid with us. What is the process? Is it even possible? I got the impression that it wouldn't be easy, and the minimum cost for a housemaid in Japan is 200k JPY. 

Relocation Questions:

1. Visa application timeline:

The current plan is to start working in January 2025.
When should the company start the application process?
The company has to apply via the local Japanese embassy at my origin. It is located in Asia. (Not in Japan.)
The company will likely apply for the Highly Skilled Professional Visa. What is the minimum salary to be declared? What is the title's position?
—> realistically your company will hire a specialist in Japan to manage the visa application. They will guide you through the process and what documents you need for yourself your partner and child.
Regarding salary range it depends on your age. There is tons of information on this on the internet. Please look for the official page of the ministry with all the details for HSP


2. Rent in Tokyo:

The office location is around Tokyo Station, so I would like to travel for not more than 30 minutes (door to door).

Which area will be recommended for me to live in as an expat and is not too expensive? Shinagawa station? Shibuya ? Ebisu ? Ginza ? Roppongi ? Azabujuban ? Hiroo ?
Any other areas you would recommend checking?
Flat size: min. 120 sq m, 3 bed rooms
What is the cost range?
Do you have a recommended agency to approach? Any other "ways" of managing this part?
—> 120 m2 and a parking lot is going to be expensive. Just to put it into perspective. I line in a newly build 2LDK 53 m2 apartment in a sought after neighborhood (Shimokitazawa) and pay around 230,000 yen rent. 120 m2 plus parking lot you’d most likely look at a house rather than an an apartment. For something new and shiny you’d probably be in the 300-400,000 yen range. For an apartment in the city center likely more. Check out web pages such as Suumo or homes to get an idea.
All the areas above except Shinagawa strike me as particularly expensive.
How are you going to go to work? I assume by train. The best recommendation is to find a train line that has trains departing from your station. Then you just need to wait 1-2 trains and can sit.
Suumo and I think homes let you search for distance to your work and for stations that have departing trains.


4. Tax Payment: There is a "ton" of information online, but I would like to ask for clear advice.
My spouse will likely be a "housewife," hence I will be the only person in the family working in Japan.
—> if you earn less than 20 million a year in essence your company is going to do all of it. If you get over that mark you’ll need to go to the tax office and do a declaration.

5. Healthcare: the company will arrange the policy. I would like to ask for any recommendations of insurance companies that are popular with expats in Japan.
—> health insurance is public. There isn’t anything to choose. You can get additional health insurance to cover the remaining part. I don’t know about that.

6. Cost of living: car and any other utilities.
What should be considered beside the "running cost," such as petrol, tax registration, car parking, and maintenance?
—> do you need a car is the first question. Within Tokyo a car is more of a hinderance. But if you plan to do a lot of weekend trips, why not. Note you must have a parking lot to be able to own a car. There is virtually no free parking in any city in Japan (except in the country side. )
Cost of living in Japan isn’t that high. But it depends totally on the type of life you lead.

To me it seems from what you are saying about your expected like style you should aim for a salary of no less than 15 million. Ideally more.

After thinking about it a bit more I think from what you described you should aim at an annual salary of no less than 20 million. That should give you a disposable income of over 15 million considering your dependents probably even a bit more.

1,25 million per month
350-400 k for rent
200 k for child care https://www.montessorijapan.com/schoolfees
250 k for salary of the house keeper (not sure if that wouldn’t be a bit higher, but assuming he/she is living with you )
500 k for your expenses.

To me that sounds like the minimum. I know 20 million is a high salary for most people in Japan, but it’s also not an impossible aspiration.