Home Window Tinting

I have two side-by-side windows, approximately 70 by 120 centimeters each, and I am looking to have some reflective window tinting film installed.
 

My goal is to reflect the morning sun and make it difficult for anyone outside to see in. Essentially, I want a mirror effect from the outside that also reduces heat and sunlight penetration.

Most window tinting I have seen is the standard black type with different levels like 20, 40, 60, 80 percent. However, I am specifically looking for a mirrored reflective type that still allows around 35 to 40 percent of light to pass through or provides at least 35 to 40 percent visibility when looking out. From what I understand, the mirrored type also helps reduce heat better than standard black tints.

I contacted a shop in my general area that usually does car tinting but also works on home windows. They quoted ฿2500 in total for both windows, which seems high for such a small job. I’ve seen that the materials themselves cost less than 200 baht on Lazada, and the shop said installation would take less than an hour. Paying over ฿2000 for an hour of relatively simple labor feels rather steep, but I could be mistaken.

The building technician where I live offered to install it if I supply the materials, and I am confident he would do an adequate job. He’s a general handyman who can fix things pretty well, including air-conditioning so I assume this kind of job would be within his level of capabilities. It would likely only require me paying him a small tip, so it would be much less costly. I am wondering whether it is worth paying a professional to do this, or if the difference in quality of the work would likely be minimal. 

I would appreciate any advice from people who have experience with this, including typical costs or recommendations for reasonably priced companies in Bangkok that could handle a small job like this of tinting just two windows in the home.