Hi, we are new to the forum and this is my first posting (of many I'm sure!)

We are building our home and are at the point of having to order cabinets. With this, we have to know our appliances. Our big question right now is microwave placement.

The usual/expected route we would take would be a 30" unit with a built-in look, next to our fridge and with cabinets above it and counter space below it. However, we'd consider 2 other possibly more economical options if they seem "ok" to do:

1 - over the range microwave where the built in would go, still with cabinets up top and counter space below. The light portion may get used, and the vent portion only if extra ventilation is needed. With the cost of these things being so much lower than the built-in, I'm not sure why this isn't done more often?

2 - countertop microwave on the counter within an appliance garage and taller cabinets above it.

For what it's worth, we'd be using the microwave fairly frequently and may be interested in a model that also does convection. We're thinking middle of the road - not a completely basic model, not one with too many features to get complicated.

Is a 30" microwave pretty much the expected/standard in a new construction? Would 27" be adequate?

And just out of curiosity... What is the usual lifespan of these things? We were thinking that, with option 2, an appliance garage would house any future microwave of any size should ours go bust anytime soon.

Hope this question makes sense. Thanks in advance.