The total number of plants depends on a) your growroom size, b) the strain you choose and c) the training method you will follow.
My tent is 90*90*160 cm. If I choose up to medium height strains, I go for SOG and although I have space for 10*4litre smart pots, I would use 9 and leave some space for heating, fans etc on the floor. Of I choose a tall stain, then I would either use LST and 4*7 or 9 litre smart pots, or two bigger pots and SCROG.
But basically you need to decide before you start the grow and design carefully your approach. When you decide just spread the runoff trays on the floor to verify how many plants will fit inside.