Definitely if your car is parked outside and not in garage. Water marks will etch into the coating if car is left under the sun after rain. Need to wash every 3 days if everyday also rain like kucing and anjing.

Higher PH can remove watermark? I usually opt for neutral PH for routine wash. Previously was using CarPro Reset, then now I switch to ecoCoat wash, more economical.

For watermark remover usually they use acidic base that is lower PH, I have a bottle that is CarPro Spotless 2.0. Works splendidly but the coating will be removed each time I use it.

Windscreen watermark I just use the copper powder to polish but I don't care all that much, I had CarPro CQ UK3.0 on it but that one didn't last. Now I just use top coat such as CarPro Reload or EcoCoat Enchancer.

Polymer type coating I think much better for our cars that our exposed to elements all the time. Especially flat surfaces such as roof, hood and trunk. Bloody headache whenever the surface becomes flat. I have given up for the past few months tbh. Just maintenance wash.

For vertical surfaces I use CQ UK 3.0 that kind of worn away after 6 months, then I recoat with ecoCoat EZ. One is ceramic, the other is Graphene Infused top coat. Vertical surfaces they hold up great, hydrophobicity still there after like 6 months - 1 year with regular wash. Never use any detailer also.

Far from pro, I think I rush through the process too much. I feel like prep for coating is not done well especially with panel wipe. I suspect got oil left on the panel after polish then I go coat. Then it wears off. Determined to do it again this month for one last time. Otherwise I will go crazy haha.

Yeah thats why I am reluctant to send it to those acah2 detailer. For those higher end ones who you know can do a good job, it isn't worth it for my cheap car either. My dad sends his car to get it "polish" every few weeks but I'm pretty sure they just wax. I don't have time to tinker with his car but I told him about clear coat thinning also.

Exterior important but not as important as interior cleanliness of course. But most important thing is mechanical health of your car haha. I spend more money on that

CarPro really sinks your money doesn't it? I was going to buy Reload 2.0 1L bottle but decided against it. Went with bead maker as weekly top coat. Then now I give up haha. plan to recoat with ecocoat ez and enchancer as weekly topper