200-400 watt lighting and start growing photoperiod plants and forget about autos.
Autos do not offer anything that can not already be acieved with superior and genetically more stable photoperiod (fem) plants.
When growing photoperiod plants, YOU controll when they flower and you can veg the plants as long as it takes to fill your grow space before flipping to flower.
Autoflowers flower when they get to a certain age, not a certain size and this is why growing autos can lead to major disappointment, spending 10-16 weeks waiting for one foot plants to do their thing.
Indoors, lighting is the biggest issue.
Spend everything you can afford on decent lighting and the results will come.
Economize on lighting and disappointment will follow.
You are basiclly trying to provide an artificial Sun.
Cheap or weak lighting is like growing under heavy cloud cover, the plants just don't get enough lumens to grow big buds.