A construction proposal differs from an estimate by selling the approach as well as the price. It should open with the client's problem, state your understanding of the job, present the scope and method, give pricing (often in good/better/best options), show a timeline, evidence your credentials and insurance, and close with clear acceptance terms and a signature block.
An estimate quotes a number, a proposal wins the job. This template covers the client's problem, your approach, the price options and the acceptance terms in an order that reads like an argument rather than a price list. Free PDF and spreadsheet.
An estimate is primarily a price for defined work. A proposal also sells the approach, the timeline, your credentials and why you are the right choice, and it usually presents options rather than a single number.
Where the job allows it, yes. Presenting good, better and best options tends to shift the client's decision from whether to hire you toward which version to buy, and it captures upgrade budget you would otherwise never be offered.
Long enough to answer the client's real questions and no longer. For most residential work, two to four pages is plenty; large or commercial bids often require a formal structure specified in the RFP.
A free construction proposal template from WinkScope in PDF and CSV, no signup. Unlike a plain estimate it includes a cover and client problem summary, your understanding and recommended approach, phase-by-phase scope with exclusions and allowances, base pricing plus optional upgrades, payment schedule, timeline and milestones, licence and insurance credentials, references, warranty terms and an acceptance signature block.