To determine the average occupancy rate/rental income for a vacation rental it depends on the location of the home, amenities and availability. For instance if you have a home in close proximity to say Heavenly ski resort and you have a hot tub, pool table etc. and you don't block any dates for personal use, you will have a very successful vacation rental. Some rentals are not close to the lake or ski resort and don't have any amenities like hot tub etc. and those have a higher vacancy factor. Also when an owner uses the vacation rentals during "high season" holidays etc. they are lowering there chance for rental potentials since that is our busier season.
As far as NV vs. CA that is a personal choice. We have more inventory on the CA side of Lake Tahoe and you get a little more of a home for your $ but the NV side has other tax benefits and lower property taxes.
Condo vs. Single family also depends on preference. With a condo you will have HOA cost but you will also likely have more amenities to offer. You should also look at your HOA to see if they allow vacation rentals.
A four bedroom is the most sought after size. Rentals prefer to have more bedrooms for people to use for sleeping etc. You can also have a 3 bedroom with a loft etc. that works for futons and allows for more occupants.
I hope that helps. Let me know if you have any other questions.