Tent: A 2 person tent divides up really well between Tent/rainfly, and poles/groundcloth, a 4 person tent breaks down each component even more. Share with a bigger tent and you should be good to go
Go in the summer months, when the temperature will be warm. I live in the Mid-Atlantic, and typically take an Army Surplus Poncho liner as my sleeping bag on trips in the late spring-early fall. In the height of summer, I bring a cotton sheet (I know, cotton is bad, but it's all I got).
If you are careful about your sleeping spot you don't need one of these. However, it's always the first "luxury" item that I pack. I won't camp without my mattress. If you can, however, I'd loan mine to the newbie friend, or use a spare/borrow one from a friend.
Most backpacking food reads like: Boil X volume water. Add powder. Stir. Let sit Y minutes. Plan to share food/utensils, and you should be good to go.
Again, double up and plan to cook/eat 2 person meals instead of 2-1 person meals.
All the friend would need is the bowl and spoon. Bowls can be repurposed from frozen dessert topping containers, large butter/margarine tubs, etc. Sure, it will fall apart after a few uses, but you can't beat the price
If you know anyone who beverages out of plastic bottles, collect and reuse them. Wash them out and use as water bottles. I've personally used 1 liter soda bottles for months before they wear out. Best part, it's free (assuming you'd drink the soda/water/juice to begin with).
Either borrow a full pack from a friend, or pack as much as you can in your pack and have him bring along the biggest backpack (daypack) he has. Alternate days.
One final note:
You can rent almost all the gear needed from a local REI. I'm not sure if you need to be a member (recommended if you will be buying a lot of gear), or if they will rent to Joe Public, but worth looking into.