Build decisions, and when they are made

[livendive]

So I'm used to tracking mandatory decisions as their own milestones in some of my work projects, as even though they may not be implemented until later in the project, upstream activities can affect downstream options. It seems to me that there are a *ton* of decisions that each builder makes during the course of each build, and while many are one-offs that don't have ripple effects, others are limited by previous decisions and/or significantly constrain future decisions. Also, sometimes not recognizing a decision results in making an unintentional but nonetheless definitive decision. Being in the waiting phase, I'm hoping to map out at least some of these decisions so that I can make them deliberately rather than default. Here are some that come to mind...input from the experience of builder's is sought.

Decision: High wing or TSI

• Timeframe: Must be made before ordering anything, as all kits are impacted
  My decision: High wing

Decision: Trike or taildragger

• Timeframe: Prior to ordering fuselage or undercarriage
  My decision: Empennage and wings both list "trike" in SlingSHOT, but I don't think I'm actually locked into that yet if I were to change my mind to taildragger

Decision: 916 or Edge Performance

• Timeframe: before ordering engine, prop, or FWF
  My decision: Assuming 916 due to cost constraints, but 918 remains an option

Decision: Anti-corrosion measures

• Timeframe: Prior to building
  My decision: leaning towards rattle can primer on mating surfaces and between dissimilar metals and nothing more.

Decision: Parachute

• Timeframe: Prior to ordering fuselage?
  My decision: Definitely want for inhospitable terrain and night flights. Planning for wires only, and adding parachute after complete
  Subdecision: Magnum vs BRS, not sure when that would need to be decided

Decision: Tail beacon vs just wingtip strobes

• Timeframe: before completing vertical stabilizer
  My decision: none yet, leaning towards both
  Subdecision: if tail beacon installed, is it red or white

Decision: GPS only (e.g. GNX375) or GPS + Nav (e.g. GTN650XI)

• Timeframe: before completing nav/vor antenna component
  My decision: leaning GPS+Nav due to limited ATC coverage in sizable portions of my normal territory and exp w/ lengthy military jamming ops
  Subdecision: If nav, install antenna on tail or in wingtip
  Subdecision timeframe: prior to completing empennage or wings

Decision: Oxygen options - bottle vs generator

• Timeframe: prior to ordering panel at a minimum. Likely needs to be incorporated into fuselage build
  My decision: leaning towards concentrators for front seats and bottle for back seats, if budget allows

Others:
Prop & controller - many options, Sling FWF kit seems customized for 916 w/ MT prop and manual prop control?
Regular vs extended tanks - Already decided on regular, as extended didn't seem to add enough to justify additional cost & complexity
HVAC options - I live in place where temps are routinely triple digits during the summer and well below freezing in the winter. I'm not inclined to worry about AC as long as there's plenty of outside air available for cooling, but a reasonably warm cabin at altitude and during the winter are important, including during extended descents.
Brakes - Beringer would be nice for short field performance (private strip is 2000' long, half grass and half paved, field elevation 4000, summer afternoon DA >6k, trees and rising terrain off one end), but I'm likely stuck with Matco due to cost
Dual G3X vs single + iPad w/ glovebox: Glovebox would be nice, but dual G3X probably nicer
Height advisor - If installing, should probably plan in fuselage build
etc...

[lutorm]

I have a few more:

Paint scheme - will affect upholstery colors and interior paint.

DIY wiring or purchase built harness - I don't know what the lead time for places like Midwest Panelbuilders are but they seem pretty busy so if going with a pre-built harness, an order needs to be put in sufficiently early. This also locks down your avionics choices.

The tail beacon question doesn't really affect much. Even if you don't know, or decide to not put it in, it would be short-sighted to not run the wire through the VS. If you do that, you can mount the light at a later time.

I thought Beringer brakes were the standard offering these days?