I represent a lot of buyers and I do communicate the value of turnkey - its worth about $20/ft hard cost, and about 2 months of mortgage payments/opportunity cost and whatever you value dozens of hours of your own time.Strong rental history is good but I do not place a ton of weight on that. 

We always set a weight and breed limit on dogs. 

If your client signed it, it carries weight.

The benefits greatly out weight he downsides. 

For rents, use the income approach: verify with two PMs, cross‑check Rentometer/Zillow but discount for aspirational pricing, and weight unit layout and parking over raw sqft when comps are sparse .

However, there is a better way.Cash-Out RefinanceIf you invest in a city where existing homes appreciate rapidly, you can grow your portfolio at a fraction of the cost of investing in a slow or no appreciation market.

If the garage is not built to support the weight of additional floors or is not adequately reinforced, it may not be suitable for conversion.3.

The macroeconomics are strong here with rapid population growth, job growth, and major companies like Intel, Amazon, Google, Facebook, Honda, Microsoft, and LG expanding or moving in, which drives long-term rental demand and appreciation potential.

And how much weight do you give to credit vs rental history?

The market here is interesting, and seems to be stalling, although construction continues at rapid rates.