A submission takes up to 350 URLs. The service sends Googlebot to crawl them, usually within 24–72 hours, and the task reads completed once that is done. Google decides what it indexes; we don't guarantee indexing.
The price is 170 credits per URL by default. The credit-cost table on the pricing page shows the live number, priced per 1,000 calls. Credits are reserved before anything is sent and charged only when the submission is accepted. Cache does not apply here: every submission is real crawl work.