I would recommend going to ScottHD's channel on coating testing. You'd find that even with most "professional" grade coatings, they don't even last for more than 1.5 years. The hydrophobic effect will usually deteriorate after a year. Any 'maintenance' you do is basically adding another layer of topper which of course will once again increase the hydrophobics again.
Most shops often advertise coatings as added scratch resistance but it really does next to nothing to protect from scratches (this really pisses me off whenever I see them saying it protects your car that way). At best coatings are an added layer of UV protection for your clearcoat, and it does make it a bit easier to clean as contaminants will not bond directly onto the clear coat.
I've personally tested a few DIY coatings myself and concluded that my money is more worth doing it myself. I've tried IGL EZ Graphene, IGL Premier, Gyeon Cancoat Evo, Fusso Coat. Each bottle of coating stated costs only +/- RM150-RM250. And you will be able to coat at least 3-4 cars and the leftovers can be kept for 1-2 years if stored correctly. Currently I'm using Gyeon Cancoat as my coating layer, and IGL Premier as my maintenance solution. Premier isn't ceramic but a variant of water based silicone, very easy to apply as it does not dry off and leave high spots, lasts at least 3-6 months before I need another layer. 
Regarding your question on the curing time, the general recommendation for most coatings within the detailing community is to allow at least 1-2 days without exposure to water after application. With the assistance of IR curing it could potentially bring it down to a day.. however that really varies between coatings and how strong your IR lamp is. If exposed to water or rain it is recommended to rinse off with water and wipe it off to prevent any watermarks from forming. Do not wash with any shampoo for at least a week to allow sufficient curing time.

Everyone starts off as a newbie so i think you should be fine if you can dedicate a few hours. I think the main problem for most newbies is polishing the car. If your car is brand new and does not have any scratches or swirls that you don't mind leaving, then you can just skip it. Usually it's still recommended to do at least a light claybar and polish so that the coating can bond properly to the clear coat. But really for my older cars I mostly just put on IGL Premier or Fusso Coat. The hydrophobics last 4-6 months and I can reapply it as often as I like without spending RM1k++..

The original price is 330 correct. But usually during big sales events like 11.11 you can get it for approx 230 with vouchers. Same goes to IGL Premier.. usual price RM200 but with events and vouchers you can get it for approx 120. I got mine off Lazada.
Osren has their spray coating as well but those only last for about 2 weeks. It's quite inexpensive and good as a maintenance topper as well.
Yes Gyeon Cancoat is quite easy to use, just make sure you don't do it under sunlight or when your car body is hot. Spray it on a dry cloth and apply, then you need another clean cloth to buff off and level, making sure you wipe any excess off.

If you REALLY want something cheap and works well at the same time you can consider Soft99 Fusso Coat. They're only about RM50 per container and will last you for many many application. It applies on like normal car wax but it's synthetic, and from testing they hydrophobic properties usually last from 6 months to close to a year.

Ah yes you're right.. setting up and tidying up after takes a good 30-45 mins itself. I find Osren's twisted loop drying towel works well but it's a little small if you're drying anything bigger than a Myvi, and also a bit pricey. Most generic ones out there seem to work fine (but do use your own judgement since some of them have lower quality fibers than others).

Better wait 4.4 sale, can apply lazada bonus..

Fusso Speed and Barrier? Yeah I've tried that too. Works alright but unfortunately it doesn't last very long. From my usage it'll stay on the hood for a max of 2 weeks only. 4 weeks maybe if it doesn't rain and you're parked indoors. Similar lifespan results to Osren Luminous Paintwork.. however Osren's seems a bit thicker but it does streak a little.

I'm currently doing Gyeon Cancoat Evo 1 layer with IGL Premier as topper.. I don't see anything wrong with using the Fusso Spray but it probably won't last as long. It will save you a lot of money though since Fusso spray is a fair bit cheaper.

For polishing that's really up to you. For maximum best effect, detailers will tell you that you need to prep your surface as clean as possible so that the coating will bond properly. They're not wrong but it really depends on what you're after.
I don't know how old your car is at the moment and if you require some claybar-ing.. you can try to put a clear plastic bag over your hands and run it over the car to see if you feel any rough surfaces.. if it's extremely rough then you might want to at least claybar and do 1 round of light polish. I really dislike those 3 stage compound polish as it removes quite a lot of your clearcoat.

Just remember to use it all up or keep the leftovers in the fridge (i think?)
Mine i used once then the cap got all harden. Couldnt even open it.. wasted half bottle..

My simple recommendations :

-Dont immediately jump to polish with machine & DIY ceramic coat your car. We go back to basics first.

-Buy clay bar to solve car paint being rough. Any brand is ok but I personally would avoid cheap 3M ones. Watch youtube on how & when to use clay bars. Can try to use diluted car shampoo as lubricant to save money.

-White cars will get black stains or turn yellow easily, advisable to get 'all purpose cleaners' type of products to clean these. If you want to save money, Sunlight dish soap diluted 1:4 with water & stored in a spray bottle works well to spot clean black stains.

-Protection products : Important to invest in a good branded spray sealant product to protect your car after cleaning. This helps keep your car cleaner for longer and avoid dirt from 'becoming too stubborn'.

-The above should be the sufficient to maintain your car, can try these out first then only go to the next level to do polishing if required.

Enjoy the process

My watermelon skin messed up coat still there , maybe need to go proper polish shop