I have done this many times. You will have a great time!
Supplies to bring, in case you haven't started your list already:
Oils: You can buy oils at your destination, so only bring the ones you can't easily find, like PKO, and the butters. Unless you have some you want to use up & get rid of.
Lye: One new bottle should be plenty, but I've also brought my masterbatch lye with me & bought more as needed
Other Ingredients: Salt, sugar, Alcohol, Vinegar, Distilled water, Chelator of choice, ROE (I keep a small bottle for each of these for travel - don't bring a large bottle if you won't use it all) You can go out & get more distilled water
Molds: Keep it simple, but probably 2 - 4 of your favorite molds and 2 - 4 individual molds
Cutting: Your lowest profile cutter & flexible plastic cutting boards (for travel I use plastic placemats)
Trays for transport: Whatever you've got that will suffice to carry from car to hotel room & back home again
Vessels & Utensils: SB, silicone spatulas, whisk, mixing bowls (3 or 4), disposable plastic cups (a few), FO safe vessel, stir sticks or spoons to mix colors, etc.
Scale(s): don't forget this/these
Colorants: Just bring a few
Fragrances: Just bring a few (you only have 4 days)
AN EXTRA SURGE PROTECTOR! You will probably need additional plug-in spots
PPE: Whatever you wear at home, apron or your soaping clothes, gloves
Extras you will need: Dishwashing liquid, Towels, rags, light blankets, or whatever you might use for insulating and for CLEAN UP, trash bags (you may not want to leave piles of soapmaking trash in the room when you leave - I don't - I carry it out to the larger trash cans down the hall by the ice machine - I like to leave the room as clean as possible so the staff don't think something weird was going on in the room)
IF there is not a kitchen sink, bring a dishpan or buy one after you get there.
EXTRA HANGERS with clips (I keep the throw away plastic ones that new clothing comes on at the clothing stores; they are great for hanging wet towels on to dry.)
Your laptop or tablet or phone or whatever you use for your soaping recipes & to stay in touch with us!
Use the Ironing Board as a table (or shelf) to keep your supplies on. (Not as a work space - too wobbly.)
Heating in the Microwave: Make sure you have at least on mixing bowl that will fit in a small microwave oven. Sometimes they are pretty small.
Encouraging Gel: I have found that inside a dresser drawer and well insulated, soap will gel just fine in a comfortable warm room. In the winter, I have turned the heater on high, with the soap mold on a tray on the luggage rack right next to the heater and left to go out for a bite, or to the store & come back to a very warm room and the soap had a good head start. Not necessary in all cases, but in the winter with a slow moving recipe, it can help.
A chair in front of the heater and plastic hangers with clips are good for drying your towels after clean up.
I have a soft-sided soapmaking carry-all type bag with wheels for the essentials, so I won't forget stuff. I have a small bag about the size of a make-up bag, that works perfectly for putting a few FO's, a few colorants, additives, small measuring spoons, gloves, & whatnot. If I want more additives & they don't fit in that bag, I have to figure out which ones are staying behind.
I have been known to bring a crockpot while travel soaping. It works well for heating oils. But with a microwave oven, it's not necessary.
If I think of anything else I've forgotten, I'll edit to include.
Enjoy!
