Building on a plot is one of the bigger projects in this game. It's almost like having a real house built as far as time & energy put into it. I think most folk get help to get their plot built, since to do it all yourself you need 5 craft skills and preferably 7. They are Carpentry, Enchanting, Fitting, Masonry, and Weaving; with Gathering and Mining added to help aquire the raw resources at maxium efficiency. I happen to be one of the crazy ones that have a character that does all seven skills (at Tier 2 or lower) and actually enjoys building. It is very satifying to me to see something I've worked hard & long on finally pop!
But, except for a few things like tents & tier 1 human houses (which look like very, very ugly brown tents) most things will take some if not a lot of time to finish (unless you're very lucky to have a crack building team available). It took from the end of the Autumn auctions, when Azure Twilight won Carmo, until recently to get most of the plot owners plots in Carmo finished. This was with me & Skirnir pulling sometimes over 12 hours a day working and all the plot owners & some others also working on them. Pop down there to Carmo and take a look to get an idea.
The higher the tier that is needed in a building, most likely the longer it will take to get the building built. This isn't always true, but it's a good general rule of thumb. So if you want storage fast go with tents, Tier 1 Human houses & silos, they don't take a lot. For machine and commercial shops stay with Beginner and Tier 1. But if you prefer bigger, better, and prettier, than plan for it to take awhile to complete or plan on alot of cash spent to attract enough builders to get it done fast.
If you do decide to pay for work on your plot, you might want to hire some high level builders for at least the most difficult work. Usually there will be someone on Marketplace Chat who knows someone or is such. For the low level work, if you don't want to contract with a builder to do it, just put the money that you are willing to pay for the work done in your construction window and then advertise in here on your shard's appropriate board and again also in Marketplace Chat. If the new, beginning builders know you are paying a reasonable amount and where your plot is, they will come. (This also does work for the high level work, but not as reliably)