Define what "We don't want to overspend money since our mainly interest is to gain high ROI." means to you? Cash flow? Appreciation?
I have looked very closely at 2 of the locations you are interested in, earlier this year - big bear and PS. I did not find "high ROI" with either unless willing to self-manage. Both locations have very high property manager (PM) costs that wipe out nearly all profit.
Also neither city is all that "friendly towards STR" unfortunately, as others have pointed out. PS bills itself as the most difficult town in the US for STR (the local Town admin for rentals told me that on the phone)- they have a nearly $1000 a year permit cost, capped number of nights you can rent (34 or 35 rental instances), someone has to be there to check-in guests, etc. Arduous, and that means a costly PM. There are several folks on this site that do well in the area, but typically outside PS, in palm desert or la quinta or elsewhere, and usually with bigger party/executive homes that can rent for big groups and big dollars, but then your up front costs are higher. I could not make the numbers work, I bid on a few properties in Feb, and glad I did not get into escrow before the pandemic. There are only a couple condo complexes that allow STR (most are monthly minimum), and one during the pandemic changed its HOA rules from 3-4 night minimums to 14 day minimums. The rules can always change, and often for the worse. I love PS but doubt I will ever consider an STR there anytime soon again.
BB is similar - yes STR are popular, yes the town is somewhat friendlier, but after doing research, including talking to a couple guys I met on this site, again I could not find a PM that was lower than 30-35% monthly fees, which eradicated all profit. I have no desire to self manage. Finding super reliable housekeeping and a local handyman (for weekly check-in/wellness visits, changing bulbs, replacing lost or stolen items, housekeepers do NOT do that stuff) is too risky unless you know a lot of people very well, built a team you trust. A first timer in the area likely needs to hire a real PM unless you live very close by. I was also looking in Moonridge, found a couple cute homes, decent priced (300-400k), but they would not gross enough to cover all the PM costs and make much profit to be worth while.
I am looking at other vacation areas instead of these.