We haven't been anywhere really since we had our 6th, but the last big trip we went on (with 7 of us) was to Disney, where we had a 2-bedroom condo, with a separate living room and a kitchen & dining table. We had more beds than we needed, with a king, two fulls, and a pull-out (two were in pak-n-plays). If you go to resort areas, like popular beaches or Orlando, you can rent a house or condo that accommodates larger groups. We live in NC & go to the beach here or in North Myrtle, where you can easily find a house or condo with as many bedrooms as you need. We never fly anymore, only drive.
For packing, I sometimes consolidate multiple kids into a single bag and just put each child's clothes in his own jumbo ziploc bag. I always travel with extra ziploc baggies of various sizes. I take a pop-up laundry hamper or 2 for dirty laundry (the hampers are $1 at Dollar Tree here). It really depends on where we go. For a week at the beach, I go grocery shopping when we arrive (or nowadays, you can order online & pick up groceries at the store to save valuable vacation time), and we prepare meals in the condo/house during the week.
Hope this is helpful; happy travels!

We are a family of 7 and have used hotels like Homewood Suites a lot when we travel. You get a small kitchen and can have adjoining rooms with pull out couches, extra beds. They also have breakfast and some evening meals. The prices aren't bad either.

There were 5 of us growing up. My parents always got adjoining rooms or a suite with a pullout couch. Then if we needed more beds they either had cots brought in or we brought pool floats/air mattresses. Little kids can sleep on just about anything. As far as packing, I remember us having one of those big roof top cargo carriers from Sears. They always packed a cooler full of sandwiches, snacks and drinks and dad would go to the store when we needed more. That way we weren't having to eat out for every meal.