Hello uaremymuse.
First of all, I should state that I know little about Las Vegas. I had the opportunity to visit Las Vegas when I was stationed at Marine Corps base Twentynine Palms, California but never did so. So, as a result, I never learned whether people go there in droves year round, or whether there are significant down times throughout the year.
I suspect, from looking at the weather, that there are times when Las Vegas gets REAL slow (scroll down until you see the annual graph):
Weather.com brings you the most accurate monthly weather forecast for The lakes, NV with average/record and high/low temperatures, precipitation and more.
weather.com
I'm not sure I'd ever want to be in Las Vegas during the summer unless I were a compulsive gambler who stayed indoors all day and all night. But if I wanted to hit the Polo Towers rooftop pool, or wanted to play golf or tennis, or just generally wanted to do anything outdoors, Las Vegas would likely not be for me.
My concern would, therefore, be #2 from my above post. If people may have been sold summertime timeshares (let's assume that their purchase may have been via a resort presentation during the spring), and thereafter realized that summertime Las Vegas may not be for them, either, they may simply stop paying their maintenance fees. If the delinquency rate is high enough, such that the resort won't be collecting all the maintenance fees they need to meet their budget, guess who ends up paying the bills: the paying timeshare owners. When the maintenance fees get raised as a result, that pushes even more people into "disgruntlement" (is that a word?) who, in turn, stop paying THEIR maintenance fees. Leading to yet another sizable maintenance fee increase......
In fact, the winter wouldn't be the best time to visit in terms of weather, either. 50s would not allow me to use that rooftop pool. And fall is kind of a dead travel season everywhere in the continental US, so that's also not too attractive. All in all, I can envision only springtime Las Vegas travelers happily paying for their timeshare but, unfortunately, they may have to ultimately pay megabucks for that privilege as they subsidize the non-payers.
So that's my initial impression but let's go to actual prospective resale purchase opportunities. From redweek:
Right off the bat, I notice that the 2 BR maintenance fees are quite high. Now I've never been to the resort, maybe it's ultra luxurious, but if not $1150 or so is a HIGH annual maintenance fee.
Moreover, redweek also has rental listings and it's obvious that the owners just want to barely get their maintenance fees back. If that's the case, I'd rather rent than buy. Moreover, I'm sure that some, if not all, would be very negotiable to be able to get even a percentage of their maintenance fees back.
On ebay, there's a week 19 1 bedroom (it says $772 annual maintenance fee) being auctioned off right now with a 1 dollar minimum and zero bidders thus far. So, again, why on earth would anyone buy from the resort? There's clearly little, if any, demand for even resales at a dollar bill.
Last, I checked Interval International for Polo Towers, Las Vegas. II doesn't let you see what the trade value for a resort might be (at least, so it seemed to me). However, I checked what was available in II's inventory for "getaways" to the Polo Towers. All I saw were studios and 1 bedrooms but, significantly, no matter what month it may have been, the rate of rent for a week was less than the maintenance fee for that week! Amazing! I checked March, June, and December for a 1 BR at Polo Towers and the rates of rent were about $700 for March, $650 for June, and $595 for December. So who needs to buy and pay $772 as an owner?
But, again, those were just 1 BRs and studios. Maybe you'd prefer a 2 BR and would be willing to throw caution to the winds about possible future maintenance fee increases. Then I suggest you negotiate with the $500 week 12 guy (or gal) listed on redweek...or just wait till a 2 BR is listed on ebay.