3. 2x 1.0HP non-inverter for two bedrooms

Consider changing to  Midea inverters AC  ...    cost not too much vs non AC

less noise  from  ON/OFF  operation
save some power .

#5 You can fit 4 compressor into what I assume is AC ledge with standard bracket right? 5th one is on balcony wall.

#1 #3 #4 you can get inverter since its not expensive.. UNLESS 3 (two bedroom) is used as storeroom nobody sleeping one.
Inverter only 1099 for Hitachi RAS-X10CJ on Lazada.

#2 2hp inverter may be a bit overkill if its not that big space. The ODU at balcony (assume there is no JMB or bylaw preventing this) should be installed where it can be shaded if possible. Although the ODU is weatherproof (and it rely more on moving air to cool) but long extended exposure to sunlight UV will make the paint and plastic parts (eg fan cover) brittle in a few years.

The difference in shaded or baked aircon ODU is ~1% - http://oaktrust.library.tamu.edu/bitstream...IC-10-10-52.pdf
This is because the ODU fan cools by air movement (it moves a lot of air). Erecting some sort of homemade "shade cover" using coregulated plastic sheet is only for aesthetic purpose (sacrificial protection) to prevent the paint from cracking up from the sunlight UV only. Though as you have to leave the fan opening "circle hole" cut out this will do nothing for the fan cover w.r.t UV exposure ya.

#5 yes individual is better for MY. Anything goes wrong the others can continue to operate. This is not SG where they only allow you to put one big ODU feeding 3-5 IDU.

1. GREE was no.1 in China market. Now overtaken by midea becoz midea had better online channel. Hai urgh noisy ODU, if its great it would have conquered its local market in MY, Gree Queen Inverter R32 spec pretty good.
2. Toshiba now not sushi but its a sub brand kinda thing under parent co Midea. Do not be fooled.
3. Get the one with heavier weight IDU ODU, more metal could mean better fins and cooling capacity. It actually depends on the series..within the same brand also got great and lousy series.
4. Shop salespeople work harder on the brand that give best commission.

Living one I presume long hours usage will have savings because its like driving somewhere..if you use a car just for 2 min drive it doesn't really save anything between an eco car or old guzzler because it haven't been able to touch the highway.
But once the aircon already cool to target temp, then it is very saving for inverter..like cruising on open highway at the speed limit, such condition you can hit the 20km/L or whatever advertised fuel efficiency the car has.

Dining area one maybe used for mealtime only then not much diff.