check the DNS (terminal: dig domain.com ANY, e.g. dig teutschaus.it ANY), check A-Record and MX-Record. When MX record points to our server configure E-Mail-Adresses BEFORE changing the A-Record. In case the NS-Server is external make sure the contact is available to change the DNS A)

save the old version of the site

menu points (click and check the path in all languages)

check all the edit buttons on the blocks (the pencil icons) that they work correctly

check external links with link-check tool (valuations, themes, partner)

social links and share buttons(links etc.)

check the content(comparing all languages available)

picture galleries (swipe, size, display, zoom)

check padding, editor (font styles, spaces, margins, padding, list style bullets for ordered and unordered lists etc.)

create .csv file, generate .htaccess, insert it in the htaccess

insert the double-opt-in and opt-out newsletter tool of cleverreach and test it

check title tags and meta descriptions

w3c check: https://validator.w3.org/ (Alt+Shift+V in Firefox with Webdeveloper Toolbar)

check MTS Impressum/colophon and footerlink produced by MTS

check privacy information and cookie bar and link.

check the tracking (event and conversion)

test 301 redirects with google site search and google webmaster tools (search console)

check the email form (validation and send to customer, who has to answer the sent email)

check the booking form (calendar, date picker, offer sidebar, S-MTS widget, (Buchungsstrecke)

page speed: test in pingdom tool

search console: indexing, insert sitemap.xml,