Planets and galaxies are usually presented as opposite requirements, which sends beginners looking for two telescopes or none. In practice one instrument serves both, and the specification that does it is the same one in each case.
Why the requirements are not opposite
Planets need resolution and galaxies need light grasp, and aperture supplies both. A 200mm instrument resolves finer planetary detail than a 130mm one and shows fainter galaxies, so the single decision that improves one improves the other. The apparent conflict is about mounts and focal ratios, not about the mirror.
What actually differs
Galaxies want a dark sky far more than they want aperture, and planets are almost immune to light pollution. So the same instrument performs very differently on the two targets depending on where you stand, and the answer to seeing more galaxies is usually a drive rather than a purchase.
The instrument that does both
A dobsonian of 150mm to 200mm. It supplies the aperture galaxies need and the resolution planets need, the mount is steady enough for high magnification, and nothing in the budget goes on motors. In this index the tabletop 130mm at $305.00 is the entry to that family and it already does both jobs creditably.
What to add later
A better low power eyepiece for galaxies and clusters, and a barlow or a short eyepiece for planets. Those two accessories tune one instrument for both targets and cost far less than a second telescope.
Questions people ask about telescope
What is the best telescope for viewing planets and galaxies for beginners?
A dobsonian of 150mm to 200mm, or a 130mm tabletop model where storage is limited. One instrument covers both targets well.
Do I need different telescopes for planets and galaxies?
No. Aperture serves both. What differs is the sky you need: galaxies want darkness, planets do not care.
What is the best telescope to see planets and galaxies?
The largest aperture you will carry outside, on a steady mount. Beyond that, a dark site improves galaxies far more than any upgrade would.