The main question you have to ask when getting glazing quotes is how they are going to do plastic trims around the windows inside and outside. Had nasty experience when windows were put in and trimmed with silicone only.
If you're looking for price, then go to a local trader.
But if you're looking for safety then go to a big company, but that will coast you like 4 times the price.
In my opinion if you live in a safe neighborhood go for a local trader. and that for the other way round.
Ask both. get a good cross sample of quotes. Ask to see previous work done by each company. For a local trader check to see how reliable he/she is.
Big companies have big advertising budgets that the customer pays for. Go for a small but well established local company, they work within a limited area and cannot afford bad reviews.
Hi like it says above maintenance of cars so why ask this question here why not in home maintenance.
Both.
UK