The delivery folks can't/won't disconnect/reconnect even if the valve is closed. Same for gas dryer.

You need an installer. When I replaced mine my choice was to do it myself (taking half a day from work to sit around and wait for them) or wait three months for an available install date. Third choice of course is just disconnect the old, let them take it and leave the new, then move it into place yourself later, whether yourself or with a plumber.

A management company should have someone on payroll to deal with this though.