How do I journalize this transaction. John Dunn storage's revenue for the past week totalled $900

Here I would record this way

If John Dunn sold for cash

Dr.Cash 900
Cr. Service Revenue or (Sales) 900

If John Dunn Sold on account

Dr. Account Receivable 900
Cr. Service Revenue or (Sales) 900

Leon invested 50 thousand

Account Receivable Dr. $900
To, Service revenue $900
(To record revenue)
It is mentioned here that if there is nothing mentioned about cash or credit then it is assumed that the transaction in credit one)