My suggestions as a tech guy & TKO type: Better Homes & Gardens Home Designer for designing spaces. It has a small learning curve and costs money, but it's flexible enough and more user friendly than other options. Pinterest.com to manage ideas / inspirations / products. Addicting. Simple. Genius. Excel Spreadsheets can not be beat for managing other information. A tab for vendor contacts and notes, a tab for budget, a tab for appliance comparison shopping, etc.

Most people can change their own oil in their car if they are at all remotely handy. Some could even venture to diagnose why it was making a certain sound. Very darn few will have the knowledge and ability to repair their own transmissions or replace a fuel pump. The knowledge is just too esoteric, even if you have driven a car every day for 40 years. It takes a specialist. Using a designer doesn't add to costs. In fact, it can save you a lot of money. They know all of the cost effective ways of putting together cabinetry to get the look you want. There are so many choices that you don't know what you don't know, and you have no idea what's you're missing by getting the input from someone who's done this hundreds of times before. Even a small semi-custom cabinet line has a spec book with thousands of choices in it. There just is no way that any lay person will be able to fully utilize the capacity of a cabinet line, while still being mindful of a budget, without having that specialized knowledge. Using a designer is not an adversarial relationship. It's a collaboration that lets your kitchen be more yours than you ever thought possible.

Why do you think it is taking longer? TLDR: See millworkman's comment - It really goes back to economies of scale, all things being equal, your house is less attractive to a sub-contractor, than someone who represents continued work. This is an absolute certainty and there are largely three ways to combat this. Hire someone who the sub will see as an opportunity for continued work to represent you (that is usually a G.C.), or pay more money so that the sub sees your job as more attractive, or find someone that has limited opportunities to work with G.C.'s (this can either be someone who does high quality work at a high price or low quality work for a mid price). Without one of those three things happening you need to anticipate delays. It is possible that your build will happen without any sub-contractor delays, however in most of the U.S. right now, that would be the exception and not the rule. Note: only a few years ago the situation was quite different so be wary of stories where everything went right a few years ago. Those delays can and do add cost, and you should anticipate their arrival and work to minimize their impact. ----- The most important thing about self contracting a project, is being honest with yourself about your abilities. That supposed savings is seductive, yet for most people it doesn't materialize, and not because it wasn't available, simply because those people were chasing savings over creating savings. The things that create savings for self-G.C.ing homes are actually the exact same things that would lead to some success as a contractor were you to enter that business. For example, a large part of G.C.ing is managing your time and schedule well, if you are excellent at managing time and scheduling, then you may create value, and if you were a G.C. that would be a viable pathway to value creation for clients. Or maybe you or your spouse are incredibly talented with construction, having done it for years, or maybe you are incredible at visualization and design so you can communicate and achieve your design efficiently. With all of these things, you are still going to encounter the economies of scale problem, but may still create some savings because of your skill set. However, most people want the savings without any efficiencies to create savings, and attempt to simply cut out a step in the value chain. That rarely works. G.C.'s create value, denying that value is a foolish move. Working to substitute your value for theirs might pay off, and it might not. But either way, they are earned savings and not simply avoided costs.

I use Rugs USA or eSale rugs for rugs (other vendors may have visualization tools, those are the ones I'm familiar with). For paint I use the Benjamin Moore Personal Color viewer. For everything else I use Word. Yes, Microsoft Word. You need to be able to insert pictures, remove backgrounds (Picture tools/format/remove background), float images so you can layer them (right click/wrap text/in front of text), and change the order of the layering (Picture tools/format bring forward/send backward/send to back/send to front). You can go a long way with just those. I generally do the paint and/or rug first in the vendor tools, then pull the resulting image into Word for furniture and art.