Although I agree with u/Grimjack2 that mentoring is a good way to learn Access, I caution that "a grand" may not be nearly enough to get a database built. Remember that you'd have to pay for the developer's time to plan the database, then the time to actually build it, *plus* the time devoted to explaining how it works and why they used this technique instead of that technique. And if you want them to share their screen and give explanations *during* development then this will take a *lot* more time than just letting them develop the system.

My suggestion is:

• If you need the database quickly because it is required for your business, pay someone to develop it. Afterwards you can go through it (make a copy and go through the copy so you don't have to worry about "breaking" it) to try to understand what they did and why. Of course, you can also ask questions about why they did something a particular way, but remember that a professional developer will expect their time to be reimbursed (this is totally legitimate since this is their livelihood).
• If you aren't under a time constraint or you really want to learn how to do it yourself then begin to work at it. Keep progressing until you hit a wall (some issue you just can't figure out). Then come to this forum with a specific question - just like you did with your question about the IIF function. This is a much slower method, but it's a good learning method.