Here are *my* must haves for a monohul, if you want to live aboard for extended stays:

Head and galley right down at the companionway.
You don’t want to go halfway through the boat, let alone pass through cabins to reach their ensuite head, with dripping wet oilies in a heavy seaway. It has to be right at the bottom of the stairs.

If you like to eat in the cockpit, it’s very nice to be able to pass food directly from the galley without walking around with it.
Also, the area in front of the companionway is usually the most stable one of the boat. Best for cooking at sea.

A separate shower stall.
Usually we like to wash from the stern but when anchorages are crowded or the weather is a little cooler it’s very nice to be able to wash inside without splashing all over the head and the sink.

Seats 4 at the indoor table without having to unfold table leaves or hampering mobility inside.

All lines, especially reefing, lead aft to the cockpit so you can do the heavy weather sailing without ever leaving the cockpit.

Walk through transom to facilitate boarding from the dinghy with your hands full of groceries. Also the nicest way to take a swim, or for washing yourself as mentioned above.

One of the smallest boats corresponding to the above whilst sporting 3 cabins, is the Beneteau Oceanis 361 that I’ve owned and loved very much. Crossed the Atlantic twice with it. You may want a Jeanneau Sun Odyssey 40 from around 1999 (the 3 cabin - 1 head layout) for a bit more payload and space in the forward cabin and twin cockpit wheels that facilitate mobility to and from the walk through transom. Otherwise a very similar boat. These are two ‘budget’ options, which seem to be the prudent choice given the description of your means. Better spend far less on the initial acquisition cost than you think you can afford. 

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Forward wind scoop: a bit of triangular canvas strung over a forward hatch between two scasions, sloping down to the deck as you move aft with a tension line to the rigging above to keep it taunt. Doubles as forward windshade and forces air down into the hatch to keep below decks cool. Keeps the air moving through. Saw this on Allied Seawind 30 on YouTube. https://www.youtube.com/watch?v=hRHskbdRFFs