By the way, did someone start it already? How is it going? Whether correctly I understand, for start of a node it is necessary to have 1 000 ardor ?
To start the node you don't need any transaction. You only need it if you want to publish your public key. The amount doesn't matter and you can also use a token, e.g. Ignis.
You can even forge with 0 ARDR deposited to this account if you lease at least 1000 from an other account.
Confirmed Balance 0 ARDOR
Forging balance 0 ARDOR
Blocks generated 0
Fees earned 0 ARDOR
Balances
ARDR 0
IGNIS 1
AEUR 0
BITSWIFT 0
Edit: Clarification: no transaction necessary to start a node.