Suica Card: how much money on?

Hello.

I will be 12 days in Tokyo and I will move not only in the main areas of the city but also nearby such as Yohokama, Odaiba, Nikko, Kamakura, Kawaguchi Lake.
1. So about Suica Card: do you think that 9000 yen on it will be enough?
2. Can I use it in the nearby cities?
3. Can I use it even in Kyoto?

Put money on it as needed; you don't need to put it all at once.

Doesn't matter how much you put on it; you can always refill or refund it! I started with 5000 yen on mine and found I had to refill it after about a week. It will depend on how much you travel, though, and the transport you take (they cost different amounts).

SUICA is very versatile and will work in other cities as well, including Kyoto. If you wish to refund the remaining balance, however, that needs to be done in Tokyo.

Yes, I know. I need only an estimate.

Providing an estimate is obviously impossible since the necessary amount depends on how much you use it.

I wrote 9000 yen because I made some calculations with single tickets. I also wrote my destinations above so you can estimate yourself. I think it should be enough anyway.

You can calculate how much each journey will cost using hyperdia. Not need for an estimate.

That's assuming you use it only for transportation AND you know exactly which trips you will make and how much each one costs.

I just put Y1000 on each morning - some days I use more some days less but that's what works for me. Also as a tourist my card isn't registered so when I lost my card accidentally I wasn't too concerned about the balance I had also lost.

I was just checking my prepaid card topping up history, and over a course of 9 days in Tokyo I topped up 6,000 - 9,000, depending on how much trains I rode, and also whether I used it only for train/subway tickets or use it also to buy bottles of water, etc., along the way. (A resident in Tokyo)

Obviously Yokohama, Kamakura, and Kawaguchi Lake would add a lot to them, and Nikko would probably require a separate ticket (for limited express, though you don't have to).

But you can start off with 4,000 or 5,000 or something just to get started; that way you don't have to worry about possibly losing the card :)

About nearby cities: is more convenient to buy separate tickets or is the same?

Among the destinations you've listed, I would just use my prepaid card to go to Yokohama, Kamakura, and Kawaguchi Lake.

For Nikko, you might want to buy a separate ticket; if you use JR, you "might" want to consider using Shinkansen part of the way, or if not, you might consider Tobu Line Limited Express, in which case you might want to get a separate Limited Express ticket (JR) or buy a pass (Tobu).

Uhm, since I just discovered that main shrines in Nikko are still under renovations I think it's not worth go there anymore. I'll evaluate other destinations.