If your budget allows you

to consider buying gift cards now for those Saturdays in the future. I know right now many restaurants are running specials that if you purchase a gift card of a certain amount you get a smaller gift card for free. If you are a member of mypoints get your gift cards through them and get bonus points for doing so. Sign up for emails from your favorite restaurants and you will get a wealth of coupons—I have a separate email address for just such things. I also get the free restaurant loyalty cards that net you free food.
Also as others have mentioned cigarette lighter devices. I have a small “ice” chest that is either hot or cold that plugs into a cigarette lighter (aka: hot spot) that I have kept many a meal warm in. Also you can use “solar” to heat things up. I’ve heated up many an item in the past in foodsaver bags on the dash of a vehicle. Park the car so the sun shines in on the pre-cooked food packet through the windshield all day and you will find you have a hot meal waiting for you.
My mil had an electric coffee carafe that never saw coffee. When dfil was a traveling salesman she would pack it full of soups, stews, chili etc and he’d plug it into his cigarette lighter as he traveled. Visit any major truck stop and you will see a wealth of cigarette lighter gadgets. WORD OF WARNING these do draw on your vehicle battery when the car is not running, so be aware of this. If you have a weak battery you might not want to use such items without periodically visiting your car and running the motor for awhile. If your drive home is long then you could “heat” the foods with these devices as you drive home and the meal would be hot when you got there.

Does your oven have a timed bake feature?

I use mine very often on days I will be gone all day. I can leave casseroles, meats to roast etc in the oven with the timer set. It comes on at the time I want it to and cooks the food. Then shuts off at the time I tell it to so nothing burns if I am late getting home. I also use this in conjunction with my crockpot and bread machine.
Ex:
In the crockpot or oven I will put a brisket to “smoke” (brisket, sprinkled generously with meat tenderizer, ¼ c liquid smoke poured over it. Wrapped up in foil and in a pan to catch the juices if I am doing it in the oven)

In the oven I put cheesey potatoes (layers of potatoes, onions, shredded cheddar cheese and a cream of soup thinned with milk baked in a foil covered pan at 350 for an hour or so if cooking alone, if cooking with a slow cook meat I cook both at 275 for the length of time the meat needs)
The bread machine has a timed feature and I use that to have bread hot from the machine with the meal.

Green beans or other veggie are put in a covered sauce pan on the burner where the exhaust from the oven comes out.—they are generally warm by the time we eat. If not it’s a quick heat up.

I make a dessert the day before.

No timed bake feature? Turkey roasters with timers on them are always on sale this time of year. You could justify the purchase with the money you would save by not eating out. Some crockpots have timers as well and you can use a crockpot like an oven for “dry” cooking. Just follow the manufacturers instructions. I’ve cooked many a meatloaf in a crockpot. They even have three unit crockpots out now that you can cook three things at once with one base.

If you really feel the need to eat out do so at lunch instead of dinner. The meals will be cheaper and the crowds are generally lower. Then eat what you would normally have for lunch for dinner. Many restaurants have the exact same menu at lunch as dinner but for a lesser price to try and get people in there during the “slow” time of day. I know when we go to some place like Golden Corral we get there just before 4 and then we get to eat at lunch price and the dinner foods are put out. This might not work if you are involved in some activities that are heavily scheduled during daylight hours.