Magic Ring of Sustenance, Arming, Feather falling, Evasion, +5 Deflection AC, +5 Insight AC, +5 Natural AC, Spell storing, major.
In italics would be requirements such as Forge Ring to craft such a ring.
Spell storing, major - 200,000 - Imbue with Spell Ability
+5 Deflection AC - 50,000 - Shield of Faith
+5 Natural AC - 75,000 - Barkskin (50,000 x 1.5 for uncustomary item slot location)
+5 Insight AC - 62,500 - Moment of Prescience
Evasion - 25,000 - Jump
Feather Fall - 2,200 - Feather Fall
Arming - 5,000 - Shrink item
Sustenance - 2,500 - Create food and water
That's your component items, now it depends on what order stuff is being added on. If you start at the cheapest and add the more expensive as you level... it totals at...
2200 + 3750 + 7500 + 37500 + 75000 + 93750 + 117500 + 300000 = 637200
If you do it most expensive and add on the little bits, or do it all at once.
200000 + 37500 + 31250 + 25000 + 12500 + 2500 + 1250 + 1100 = 311100
That's using the guidelines quoted below, a DM might decide to shoot for the middle of those 2 numbers, so around 474100... or 475000. The reasoning? You're not adding one or two or three things here, you're adding eight.
It would take a normal crafter using no trickery...475 days to craft this ring, or 312 days or 638 days depending on the market price your DM chooses to pick. It could be crafted faster, for a lot cheaper with some crafting trickery, but a standard wizard with no reduction feats making this for example? well, using 475000 as a guide.
237500 GP, 19000 XP, 475 days.
The most important rule for custom magic items? The DM has the last say. He can say what is reasonable, what's unreasonable, he can work it out by guideline like I did there and decide to double it if he sees fit. As he could say 'there aren't many crafters good enough that would spend 2 years making one ring, therefore they cost double this to commission.'
The above crafting may contain mistakes such as forgetting to include the cost of a masterwork ring to start or if the spells have XP costs / Material components. etc.