Freezing and dehydrating are the other options I use.
Freezing: You can wash, core and freeze them whole - easy, but takes up a ton of room. To keep from filling up the freezer with big frozen tomato balls, you can wash, core, and cut into quarters. the more seeds that 'drop out' the better - we don't mind a few seeds and we don't skin them - your choice. Pack into freezer bags. Once frozen, take them out and thaw them. Pour off the water and you'll have reduced the storage to about a quarter of the bag with just tomato 'meat.' Now you can make other decisions.
Freeze now in quantities you are likely to use for cooking. Cook them with seasonings (spagetti sauce, pizza sauce, whatever) and freeze. I cook mine down in a big electric oven and use a stick blender to blend it all into smooth sauce. Smaller quantities could be done in a regular blender or food processor. Then freeze all seasoned up. Freezing and thawing is the trick to saving space and saving time because you don't have to cook them down for hours to get rid of the extra water.
The other option is dehydrating. In pieces like sun-dried tomatoes or cooked down and dehydrated as a leather.