If you grow from seed each grow, you'll have to get seeds for each grow. You can force a female to produce male pollen if you'd like (look into silver thiosulfate and colloidal silver).
A few things to consider —
1. If you imagine you'll be making your own seeds and that will be your source, get another tent, light and plenty of filters, because if you or a male plant start spreading pollen around, everything will be seeded. Some people like smoking seeded weed, but most do not.
2. Many growers grow from seed, take clones of each plant and keep the clones of the best plants they find. Then grow from clones after that. You will need a second tent, light, etc. to keep clones.
If you think it's too expensive to buy seeds each grow, can you afford a second tent?