@Ruby
It does sound like getting custom tilesets is a very costly purchase. I agree that, if someone is intending on making a huge commercial game, it is probably worth commissioning custom tilesets. But if they are making that type of game, I'm sure they have probably at least $30,000 budgeted for resources, from music to artwork.
Take your favorite professional RPG and look at the end credits. Let's say each artist gets paid $30/hour. Now, let's further say each music or graphic artist works full time on just that one game, and they worked on the game for 6 months. That's $31,200 per artist for their time.
So I think $1,000 is probably way too low for the custom tileset.
It sounds like the artist has never made VX Ace tiles before, and has no idea how long it takes to create them.
Personally, I'm very grateful for the Resource Packs, since I'm not making any commercial games and their quality is far, far better than I could ever hope to draw on my own (Stick figures anyone?). But, then again, we all have our own unique talents.
If you really want custom artwork, what I'd recommend is just commission a few key pieces, like a few key non-autotiles in the B-E tileset, and perhaps some custom player character sprites. If you use those strategically, they can add a nifty custom look to your RPG without breaking the bank.