You can get a large Breville toaster oven - they work really well and get good reviews. They're not as large as a wall oven or range oven but they come in 3 sizes and the large one is okay.

Thanks - but I need it for things like huge turkeys and the Breville isn't near large enough. Any other suggestions?

Vents in kitchens are relatively new--my mother's house never had one, so assuming you can crack open a window in your basement, probably it would be fine. Code is another story--don't know.

I suspect that you will not be allowed to put a 240V appliance in the basement by housing codes. This is only a problem if the appliance causes a fire in the house and your insurance company declines coverage since you did not get a permit for a kitchen. In most locales a "wet bar" or kitchenette is permitted but special dispensation is needed for a kitchen with 240V or built in oven/cooktops.

On the front page of the Target ad this week there is an Oster 18 qt self basting oven roaster for $27 that they advertise as being able to hold a 22 lb turkey. If this is big enough maybe you can use the Breville with occasional use of this large roaster.

Suggest you check with your city's bylaws and building code depts and your insurance company first. You will of course be getting a permit anyway to put a 220v line in the basement.

Free standing oven?
Usually a restaurant or institutional kitchen item which usually requires 208v 3 phase power.

Ventilation is not required, by code or otherwise. It's just a nice thing to have. Countless apartment dwellers and owners of old homes get by with no vent. There's no need to avoid using the burners on the 2nd range, though you probably want to do the really greasy/smelly stuff in your main kitchen where there's ventilation.

Basements with electric dryers already have 220/240 Vac wired to them. Of course, for a separate appliance like a range or oven a separate cable and breaker are needed.

240 Vac wiring in the USA is not typically inherently more dangerous than 120 because each 240 conductor is 120 Vac to ground. If one insists on grabbing each conductor, however, the result will be four times as much current through one as grabbing a 120 conductor and the ground conductor.

Most electrical risk is due to inadvertent 120V leakage to some metal that isn't grounded and then touching that metal while grounded. This risk is reduced by the use of GFCI breakers, which as I recall are now required for branch circuits of the type the OP's plan requires.

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