the reason you keep getting bad contractor bids is not bad luck.
It is that you asked for an estimate instead of issuing a bid packet.
An estimate is an invitation for guesswork. A bid packet is a filter. Full scope, timeline, budget parameters, and a qualification checklist: licenses, insurance, bonding, experience. Everyone bidding is working from the same document and proving they belong in the conversation before they ever submit a number.
Most investors have never seen a real bid packet. Most contractors respect and value detailed and knowledgeable clients.