Thank you everyone. I definitely have all the safety stuff. Carbon detectors and fire extinguisher included. Meds are all in a lock box in our bedroom which is on a different floor. I have a small first aid kit up high in the playroom and a small ER room in the linen closet lol.
I did some more research and decided to use crib mattresses for nap time for older kids. They are fairly cheap in comparison to other alternatives. I have also ordered high chairs from Ikea. A few people here have posted about them. I also have a dedicated kitchen table that I will use for the kids and the chairs have nice big seats for those that are too big for the highchairs. Will get boosters as needed.
As for separating the older kids from my daughter, I'm not too worried. She's a little brute. I still have her "trapping devices" like her exersaucer and jolly jumper when I need to keep her stationary.
I think I'll get some more washcloths!
Its not so nice where I am! It snowed all day. Our backyard is a mess due to having to put in weeping tile last fall. Once the snow is gone, ground is thawed and mud has dried we are landscaping the whole thing so we will deal with out side then.

I'm just worried the toys I have are not going to keep the kids entertained?? I guess only time will tell!