The cheapest quote is not always the best, and the most detailed is not always the most honest. A short list of questions shows which quote is solid.
Is the scope clear?
A good quote says what you will receive in terms you can check. Vague lines such as full system development leave room for disagreement.
Ask these questions
Put them to every supplier you consider.
- What is not included in this price?
- How are changes to the scope priced?
- What testing is done before delivery?
- What support is there after launch?
- Who owns the code and the data?
Compare like with like
Two quotes with very different prices often cover different things. Line them up item by item before judging the price.