A) Check reviews & ratings

B) There isn't much to do in SJ del Cabo thus I recommend going into Cabo San Lucas for night life (Cabo Wabo is in Cabo San Lucas). Also, many of the San Jose del Cabo resorts offer either a complimentary shared shuttle service a paid shared shuttle for about $20USD each way. This is a better alternative to the $30-40USD each way for a taxi.

C) I've stayed at several AIs. Even w/gratuities often included in rate, I tip the porter & housekeeper as I like extra towels and my bags promptly delivered. I also tip the bartender at the pool bar to ensure I receive top-shelf liquor in my cocktails. If the restaurants are buffet or self-serve style and the waiter only brings/refills beverages, I just tip a few dollars (USD, not pesos). About $10/pp a day should suffice in tipping at an AI provided it's a gratuities included resort and you'd like better service...otherwise standard tipping rates apply. BTW- unlike other parts of Mexico, USDs are widely accepted in Cabo San Lucas & the resorts/hotels.

D) I have a condo in Cabo San Lucas (Marina area) which is about 30 minutes from San Jose del Cabo & the Crowne Plaza. I always take the general precautions I would take anywhere I travel (not leaving possessions unattended, flashing currency, wearing expensive jewelry, etc). The only people I know who have had problems are the ones who were highly intoxicated thus an easy target for pick-pocketing, price gouging, etc.
In Cabo San Lucas, if you stay w/in the Cabo Wabo and Marina area you should be okay.

Most of the beaches are not suitable for swimming as there is a heavy under tow. There have been many drownings of tourists who do not heed the warning signs. I recommend going to Medano Beach (located in Cabo San Lucas) for swimming. It's a safe swimming beach w/a lot to do including water sports. Billygans and the Office are located on Medano Beach and often have all day happy hour and good food.

There's a shared shuttle from the airport to San Jose del Cabo for about $14USD per person. You can pay upon exiting the airport or arrange it w/your hotel ahead of time for just a few extra dollars. Also, right after you go through customs, you may be inundated by timeshare salespersons offering you free transportation to your hotel...bypass them and just get the paid shuttle service.

I hope this helps.