Start with relevant experience, not the length of the client list. Ask for a couple of case studies that resemble your stack, and then ask specifically which engineers actually built it. An honest provider is happy to connect you with the engineers. Evasive answers at this stage usually mean the demo work came from somewhere else.

The paperwork needs more attention than the sales deck. Three sections matter more than the rest: ownership of the code, confidentiality, and notice periods and handover. Everything produced should transfer to you on payment, .net development company together with documentation, pipelines and deployment scripts. Look closely at language that leaves framework code in the vendor's hands, because this is frequently the part you cannot replace later.

Ask how they estimate. A credible estimate comes with a written set of assumptions, a breakdown per feature and an explicit range. A fixed-price contract is only reasonable when the scope is genuinely frozen; when the scope is still moving the vendor adds a risk premium and you pay for uncertainty either way. A time-and-materials model moves the risk back to the client, so it requires visible weekly reporting and a spending cap.

How the work is run matters more than the number of developers. Establish how a new requirement enters the plan, who writes the acceptance criteria and how quality assurance works. A mature team should be able to walk you through running software development companies in qatar rather than status reports. Acceptance criteria in writing are your only real protection against the it-was-never-in-scope conversation.

Finally, think about the day you no longer need this vendor before it becomes urgent. Ask that the repository stays on infrastructure you own from day one, and that the documentation is refreshed in every sprint. A vendor with nothing to hide accepts it without argument; resistance at this point reveals a great deal.