Getting right to the point, many (possibly even most) software/web developers will simply hand you the deliverable upon project completion and call it a day. The tools and processes used are often held back, forcing you to always go through them for updates or eventually argue with them to get what you need. Although the former may make a bit of business sense on the consultant's side, I'd argue that this methodology is terrible.
Lately, I've been approached by multiple organizations in a really tough spot: they were working with a developer and something tragic happened to him/her mid-process. The organization had been kept in-the-dark about the tools, processes, tasks, online accounts, etc. necessary to pick the project back up. In the end, this often forces the clients to restart from square one.
The following is a list of topics to discuss with your consultant before the project even starts. During the ongoing work, require that they keep you in the loop. At a bare minimum, you should at least be able to 1.) find a replacement with the necessary skills and 2.) pick up where the project was left.
Again, some consultants will be reluctant to provide the above, or at worst will refuse outright. However, I'd argue that their level of irresponsibility is extremely risky. Tragedies, breaches of contract, and other negative circumstances can happen. Be prepared to keep your project on track!
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