When I design for new construction, here is a general order of things I do (specifically as a designer):
***Edited to add that appliances should be selected FIRST, before cabinet layouts are finalized!
1. Space planning, including framing changes and cabinet layouts. All cabinet layouts need to finalized for plumbing centers (toilets and sinks). Your cabinet layouts should be determined by the actual cabinets you are using. Custom cabinets can be altered to accommodate the framing, but stock cabinets cannot. This phase includes ceiling design and other architectural elements, like columns and fireplaces. All framing happens first, unless you want to pay your framers to come back multiple times. Walkthrough with the framer.
2. Exterior finishes. Select these with your builder so that everything can get ordered. This will include siding, stone, brick, roof, windows, etc.
3. Plumbing selections. Because much of the plumbing goes behind the walls, this step needs to be completed early to avoid backorders. I select all plumbing at the same time, but I suppose you can just purchase the valves and finalize the rest later if you absolutely have to. You will need to communicate to the plumber what kinds of devices will go in the showers and where exactly they should be placed. Walkthrough with the plumber.
4. Electrical plans finalized. Wall sconces should be selected so the heights can be placed appropriately. Pendants over surfaces should also be selected so they can be placed appropriately. Walkthrough with the electrician.
5. Millwork selected and ordered. Includes trim, doors and door hardware. Any wainscot or applied molding should be designed and communicated to the installer. Walkthrough with the millwork provider and installer to review your selections.
6. Wood floor selection. Be prepared to communicate a general desired finish so that the correct flooring can be ordered (ie, White Oak or Red Oak, solid or engineered).
7. Finalize cabinet finishes/door styles and order. Lead times can be lengthy for cabinets and you do not want to delay the project waiting for them. Review all details with cabinet provider, including special drawer inserts.
8. Tile and countertops selected. Tile should be ordered early to avoid backorders. Tile layouts need to be determine and communicated to the installer. Grout needs to be selected. If working with natural stone countertops, slabs should be tagged. Walkthrough with tile installer.
9. Staircase design. Communicate the look you want and select the stair parts like newels and balusters. Staircase meeting with fabricator.
10. Order all lighting fixtures. Ideally, order fixtures from somewhere it can be all warehoused until delivery. You do not want light fixtures sitting at a job site.
11. Select carpeting or LVT. Meet installer on site for measure of spaces.
12. Paint schedule, including colors and finishes. Wallpaper selected. Walkthrough with painter and/or wallpaper installer. Order wallpaper.
13. Finalize floor finish. Meet on site with finisher to review samples on floor.
14. Cabinet installation. Walkthrough to confirm everything is correct and undamaged.
15. Countertop measure. Communicate edge details and reveals to the fabricator. Approve countertop fabrication layouts.
16. Countertop installation. Be on site to ensure all tops are correct before installation.
17. Backsplash installation.
18. Shower door and glass. Communicate details such as shower door swings, handle style and finish. Where you want flat applied mirror and where you will do hanging mirrors. Walkthrough with shower door fabricator.
19. Order mailbox and address numbers. Communicate placement.
20. Light fixture heights. Meet installer to place the heights for all hanging light fixtures.
21. Mirror and bath accessory placement. Meet installer on site to place things like towel bars, TP holders and hanging mirrors.
22. Final walkthrough to note any required touch ups or issues.
Throughout this entire process, you are also managing the BUDGET. Making selections and then pricing it all before actually ordering. This process can require multiple reselections of materials to keep within the budget or allowances. As a designer, this can be the most complicated part of my job and requires a lot of experience to select the right material for the budget and to anticipate actual costs. This has been made even more challenging by the multiple price increases we have experienced the last few years. So while you say there was no room in your budget for a designer, I would suggest that you risk spending a lot more money and making critical mistakes by trying to accomplish the list above within your budget without the education or experience to do so. Do not assume the GC or trades will be able to fill the role of designer. It's still early enough for you to seek out an experienced professional. This is likely the largest investment you'll make and a qualified professional designer can safeguard that investment.
Q