Resident expert here.
The 1997 Hendrix Tribute
strats were full left handed guitars turned upside down. Those were only made in Olympic White and came only with maple fretboards.
The 1997-1998 Voodoo Strat and the 2001 '68 Reverse Headstock Strat (same guitar as the Voodoo strat minus the Hendrix-engraved neckplate) came in Olympic White, Black, and Sunburst, available with either
maple or rosewood fretboards.
I say jump on it. I don't think I've ever seen one with
a certificate of authenticity. At least not on the second-hand market. So that's not too weird. If it is real it should have all the typical features you're familiar with. It should have a TN7 serial number regardless
of the year in which it was made. All the necks were made in 1997, even though the various projects got halted at some point because of legal troubles. Thus some were not released until 98 and after 2000.
If it's all original it should include the ACE style guitar strap and a white curly amp cable. The case should be black tolex and it should be the type with the Fender amp badge on the outside.
If it has all these things, it's more than likely real/I don't know how else to assure its authenticity short of taking it apart. The only other thing you can check, is if it has the tremolo cover removed on the back, there should be either a V or a 68 written in permanent marker on the body underneath the springs. Anyways, it wouldn't make sense for someone to go out and buy the case and case candy to try to fake it, seeing as how the straps alone can run hundreds of dollars, as well as the Hendrix-engraved neckplate.
As far as the guitar itself- these things are unique. I am personally obsessed. Tonally, they are distinct from any other strat you will play. And if you are a believer in "vibe", then it seals the deal. I love everything about my Voodoo Strats/68 Reverse. I literally can't stop buying them.
Regarding the investment value, they will definitely appreciate. They are simply rare in comparison to a lot of other models out there, and they happen to be attached to the name of the most iconic stratocaster player. I would try to talk them down on the price, but I know a pristine Voodoo Strat with all case candy included can go for up to $3000-3300 USD. Highly used ones will hover around $1700-2200 USD. Based on eBay auction-watching alone, I can say that mine have definitely appreciated in value since I bought them not all that long ago.
On the other hand, these things beg to be played. Sure, don't take it out and gig it if you're trying to preserve its pristine condition for investment value. But the value appreciation is marginal enough that you won't change anything playing it around the house. In fact, you should. I tried the whole investment thing. Didn't work out. I gigged both my white one and my sunburst one. The black one was pristine enough that I decided to preserve it, but I'd almost rather sell it than see it sit.
Bottom line, if the only reason you're buying it is to try to turn a profit, there are better ways to do that in much less time. You're going to have to hold onto it for a long time to justify that. If it's not vintage, people generally aren't collecting it solely for investment value. On the other hand, if it is a guitar that really interests you as a guitarist, and the fact that it will appreciate in value is simply another reason in favor of pushing you to get it, I say go for it. You will not regret it.
[edit: the Cypress Mica Strat in the pic is a one-off, not a Voodoo strat of any sort. The black and the sunburst are both Voodoo Strats, and the Olympic White one is a '68 Reverse Headstock]