1) At LEAST three days.
A) No. You will waste a lot of time driving in and out of Haifa traffic every day on your way to the Galilee. (on another forum, a tourist who ignored this advice has now posted a trip report acknowledging that using Haifa as a base was a big mistake).
B)It depends on what you saw (and didn't see )on your previous up north AND what you are interested in, e.g. I would recommend a day in Akko but maybe you did that last time. Please post more details.
2) Definitely rent a car. There is no need to spend so much money on a guide as all sites have signs, brochures, audioguides or provide their own tours. You can also download a lot of information from the internet in advance.
3) This depends on where your daughter will be and what your interests are: are you religious or secular ? do you like restaurants, entertainment, beaches, etc ? Rather than hotels, you may prefer to look for holiday rental apartments, one week in each city.
4) You have to ask the tour guides or tour companies what their terms are.
5) Since you have already toured the country with a private guide, I doubt that you would be interested in the standard one-day tours given by Egged Tours, United Tours, Abraham Hostel, etc. As I said above, most places can be toured on your own.

I think you first have to decide what you want to see on this tour, then we can figure out the best way to organize it.

Thank you so much for replyingII
Since the first 2 weeks are up in the air, it's best for me to focus on itinerary after the games. Yr response/suggestions will help us choose the return flight date.

1) We never went to the northern region during our previous visit. We only toured the south. So we would like to see as much of the North as possible.
Netanya, Caesarea, Haifa, Akko, Tiberias, Roche Hanikra, Safed & Upper Galilee, Golan Heights. What did I forget??
As far as our interests and backgrounds, we are non-secular Jews (mixed marriage).
Definitely want to tour some important historical sights, although prefer to explore/experience more of the culture; shop the markets pottery, arts, food, tour wineries, diamond factory, springs, hiking, boating, biking, open to any/all adventures.
2) Based on this, how many days would you recommend??
3) should we return from the north straight to the airport or is it more convenient to stay overnight in Tel Aviv (closer to airport)

Again, I really appreciate your help!!!!

If you have never been to the north then I revise my suggestion to AT LEAST 5 days. It also depends what you will be doing during the two weeks of the games, e.g. it is very easy to go to Akko as a day trip from Tel-Aviv by train. But assuming not, I would plan an itinerary roughly as follows:
- day 1 : Caesarea, Haifa. overnight Akko
- day 2 : Akko, Rosh Hanikra. overnight Akko
- day 3 : Safed, Capernaum, etc. overnight Rosh Pina
- day 4 : Upper Galilee - Tel-Dan, Banias, etc, etc. overnight Rosh Pina
- day 5 : Golan Heights - Gamla, Katzrin, Hamat Gader, etc. overnight Rosh Pina
- day 6 : Bet Shean, Belvoir, etc, etc.
You can drop Netanya from your list and add Bet Shean.

Your itinerary depends on what your interests are. Here are some web sites with suggestions:
- National Parks:
http://www.parks.org.il/parks/ParksAndReserves/Pages/default.aspx
Click on [Search] and look for the Parks in the north. Click on [Entrance fees] for details of their discount ticket.

- Museums: a list of all the museums in the country:
http://ilmuseums.com/

- The govt tourism web site:
http://www.goisrael.com/Tourism_Eng/Pages/home.aspx
Click on [by region] and [north].

- Akko tourism:
http://www.akko.org.il/en/

- Bahai Gardens:
http://www.ganbahai.org.il/en/

Other sites:
- Tel-Aviv "City Pass" discount ticket:
http://www.iandm.co.il/Campaign/TLV/city_pass/city_Pass.pdf
- Tel-Aviv free walking tours:
http://visit-tlv.com/?CategoryID=191&ArticleID=480&Page=1
- "Time Out" magazine - Tel-Aviv edition:
http://digital.timeout.co.il/english/

A few comments to the suggestions you received.

a. why drop Netanya? Personally, there is a limit to the number of archeological sites you will enjoy in a short time period. You are doing Caesarea and Akko. Beit Shean, can be absolutely brutal (weather wise) in August. Worse than the other two by far. Netanya would provide restaurants and beaches--a down time

b. Even though you toured with a private guide 15 years ago--a lot has changed. I think you need to also spend time in Jerusalem ( you will be there anyway for opening ceremonies) to see what is new, different and updated.

c. I would want to be closer to the airport than the north for my last night--but that is just my preference.

Elkaz:

a. They will be in Tel-Aviv for at least a week before heading north, during which time they will no doubt visit the beach often and sample the restaurants. Their trip north is for sightseeing.

b. They are also planning a week in Jerusalem. I agree that a private guide is a very good idea there.

c. It depends what time your flight leaves. Note that you have to be at the terminal 3 hours in advance and you need to allow about an hour to return the car (you have to take a shuttle bus from the car return building to the terminal building). So if your flight is in the morning you should be closer to Tel-Aviv for your last night; otherwise you can drive down from the north.

"b. They are also planning a week in Jerusalem. I agree that a private guide is a very good idea there."

who are you agreeing with. I never said that they should get a private guide. Please do not put words into my mouth.

Your other statements--I disagree and I totally understand what they are doing. --but have an opinion which is different than yours!

Forgot to add--and there is no way to edit here

Driving down from North--what happens if the car breaks down--not likely--but could happen--I would not want that to happen the day of my flight!