Twenty players means ten simultaneous games. The minimum that has to arrive at the venue:
Packed sensibly this comes to two crates and a bag - one person can manage it in two trips, two people in one.
One more habit worth building: number the sets. Write a number on each piece bag and on the matching board. Then a missing piece is traced to a set rather than to the whole collection.
Run it before leaving home, not at the venue:
The full preparation checklist covering everything else - the organizer's checklist.
The moment equipment actually gets lost is not on the way there but on the way back, when everybody is tired and helping.
Carrying crates every week is a real cost, and there are ways around it.
And one thing that no longer needs carrying at all: the paperwork. Pairings, standings and tie-breaks live in an app rather than in a folder - running an event from a phone.
Ten boards and ten sets of pieces, ten clocks (or at least five), spare batteries, table numbers, a registration list and pens, and an extension lead. Packed properly that is two crates and a bag.
In plastic crates rather than bags, with pieces bagged one set per bag, boards rolled and stored upright, and clocks separately with padding. Number each piece bag and its matching board so a missing piece can be traced to a set.
On the way back, not on the way out: everybody is tired and helping. Count against the same list you loaded from, check under the tables, and do not let one person pack up alone.
Dry and not cold - garages and balconies warp wooden boards and kill batteries. Take batteries out of clocks over long breaks, and keep the whole inventory in one place with one person responsible.
Ask the venue to store two crates - many will, especially if your evenings bring them customers. Failing that, borrow from a school or federation, use the venue's own boards, or at a small club ask players to bring their own sets.
No arbiter skills required. The app takes over the part that usually stops people from running tournaments at all: who plays whom in each round and who finishes first.
The bot is constantly improved based on real tournaments. If you need a feature that isn't there yet, message the developers right inside the bot with the /support command. Many features appeared exactly because organizers asked for them, and useful ideas get added quickly.
Equipment - equipment for schools, electronic boards. Organizing - logistics, the checklist.