There is one investment that I really recommend, especially if you know you'd like to homeschool long term--a good laminator. They can be a bit pricey, but there are ways to get them at 40 or 50 percent off. Several national chains of craft stores regularly have 40 and 50 percent off coupons and sales, and I used one of those to purchase a laminator/bookbinder combo for about 60 dollars. It sounds like a lot until you figure in how much you can do with it. I have laminated things like the 100s number chart, special artwork, sent leaves through the laminator for a special project (that might have tested the poor machine's limits). I have also made my own hard cover photo books like what you would get from professional photo sites. There are some other brands that just laminate, so if the book binding doesn't appeal to you, then you could probably get a quality laminator starting around 35 dollars (with a sale coupon).
My most recent project for the laminator was a set of 100s cubes, 10 strips, and 1s cubes. I laminated them and put magnets on the back and now my son has a math manipulative for learning his place values. I plan to put them on a magnetic dry erase board and then he can move them around and write answers directly on the board. I have also laminated flash cards that I have printed from online and an alphabet strip to help him with his alphabetizing worksheets.
Overall, a laminator is really worth the price, especially if you can get it half off.
Editing post to add: I just realized that it's ok to mention store names, so i will tell you all where I got the great Your Story laminator with a coupon--AC Moore. Bad news is that they aren't located everywhere, so I googled and saw that Walmart carries it for only a few dollars more than the 40% off price at AC Moore and you can get it shipped to your local store for free :)