"If Right now I have a limit of 10 items per a mouth will a regular store give me the option to post 150 items per a month "
Sorry, but no. Even if you open a store, it doesn't change your selling limits (if you have them).
This will explain what you can do to raise your selling limits:
Selling Restrictions - eBay
Until your limits are raised, it would probably cost you more in fees if you were to open a store.