I think due interest rates and lack of full master bedroom we can’t get it off the market .Any advice on what we can try? 

What is their nightly rates and occupancy?

Valid reasons might include increased operating costs, property improvements, or market trends.Fairness and market rates: Rent increases should generally be reasonable and in line with market rates for similar properties in the area.

Interest rates change, regulations change, in CA lots of fights happen, inflation happens, and just so many headwinds to fight thru as a developer. 

Code § 7701 - Definitions, my understanding is that the answer is NO, but maybe I am wrong.As the actual rate of withholding is 15% of the sales price, and as the refund (if any) would be "within 90 days", it can be a major setback for my company´s flipping cash-flow because 15% is way higher than the taxable income (and of course than the tax itself), so we would be in the necessity of capital injections to flip the next properties.If any of you have comments on this, it would be very helpful.Thanks in advance

While sellers or wholesalers may sometimes dictate the title company, having your preferred option ready can be advantageous.To vet potential team members, engage in conversations and assess their responsiveness.

My question is, would adding a shed to these properties increase rental rates?

I am going to give it another 12 months to see if rates come down, as my first mortgage has a 6.25% rate and my second has an 8.125% rate.

Many cities are regulating who pays for screenings and how much they can charge because many landlords will charge applicants a fee and then they'll take 50 applications, but that's a whole different conversation. 

For wholesale purposes you will find distressed properties that when fixed are still in affordable price ranges for end buyers especially with where rates are, or work on DSCR products.