How can I evaluate the accommodation needs of a client?

Hello,

I have a client who has a website (duh) but their web traffic is very strange because it is completely limited to two blocks of ten days a year. They organize trade fairs. The shows last 8 days, from Saturday to Sunday, and are spaced 6 months apart. At their last show, their site crashed. It was my first time as a web developer at a salon. They fired their previous developer / host and it was a bit difficult. So there is no way to know what was the previous hosting configuration. When the site collapsed, I took a closer look and discovered that it was terribly built. There was a full resolution background image of about 4,000 pixels wide and a host of other elements that made the site very heavy. So, I did a ton of work to tweak the site and make it as light as possible and it crashed again. I have therefore set up a CDN to further lighten the load, which is still crushed. This time, I went to buy a very large hosting environment and moved the site there. This has been the case, but at this point I am losing about $ 75 a month on their website because I pay more for their accommodation than for me.

So, what I really need, is a way to assess their hosting needs. I am a web developer and I feel like I am good enough, despite some obvious mistakes as described above, but my knowledge is simply insufficient in hosting. The only server specification that I can confidently evaluate is storage space. I have no idea of ​​RAM or transfer (is it the same as bandwidth?) Or anything like that. I guess what I'm looking for is either a tutorial that will help me learn how to do this assessment, or someone who is willing to ask me for relevant information and make recommendations. I have access to their Google Analytics account and so I should be able to provide the specifications we need. Thank you very much in advance for any help offered.

Better,
swani