Domain transfer. What problems might arise?

Question

Domain name market

The customer wanted to remake the site from scratch. I propose to create in parallel a site that is disabled from indexing and copy content from an existing site, from a working one now. A site selling equipment and advertised in Google and Yandex, closing the site for a week and doing it right on the spot is unrealistic, we will lose customers.
Tell me, if I create a similar site with the same content as on the working site, with the same page addresses (except for the domain name), then later, if I switch the domain to this newly created site, will everything work as it did? Titz won't disappear? After all, links from third-party sites to mine will go to the same addresses ..
What problems can I face? What will happen to the tits domain, how will it affect the performance of the site in general? I would like to create a site so that there are old page addresses and there are no losses in terms of characters and positions in the search. What do you suggest?

Answer 1

if everything is done as you described, everything will be ok,
you just need to close the site from the outside through the password so that the search engines and someone else does not go to it while it is in development, I would not trust the robots file at this moment

Answer 2

If the url doesn't change then there shouldn't be a problem. Links are indexed.

Answer 3

with the same page addresses (except for the domain name)

Tits will disappear because it is issued to the domain, you can glue the domains, but they will not stick together for you. you need absolutely identical sites both in design and content.
In general, in order not to lose positions in the search, it is necessary to redo the old site, but even then, even with a redesign, positions sometimes jump.