When you think you have enough chains or straps on the load, add a couple more. At least till you know the loads and what they require.
Be careful asking for advice, some drivers take short cuts. If you have any doubts, add more, as you are ultimately responsible for your load.
If you ever do lowboy,here is how to secure an excavator. 4- 1/2 chains and binders at 4 corners and a 3/8 chain and binder over the boom. We lowboy drivers don't mess around with that lightweight 5/16 stuff. :lol: