Bids offer, make gig workers compete between them to get the gig at the best possible price. You can also choose through their personal qualities e.g., profile, communication skills, trust, reviews, and gig completion rate.
Quotes are also good, especially if you unclear about your gig (Cost, what is best for the gig) and want to have their professional advice before proceeding, services they offer, number of revisions allowed, or even warranty.
Quotes are most preferred for onsite gigs, as site visits are paramount to get an accurate evaluation of the gig.
But, you may not get the best price as there is no open competition.
When you have the proposal price and valuable advice, you can list the gig as a bid with all the necessary information to get the best price.