Need someone good with Shopify to fix our store, its a bit of a mess right now

Ok so here's the situation. My wife and I started a Shopify store last year (we sell handmade candles and some home fragrance stuff) and it did way better than we expected, which is great, but now the store honestly can't keep up. We built it ourselves off a free theme and youtube videos so it's held together with tape at this point. Here's what's going wrong: - Checkout randomly breaks on some phones. We've had customers email us saying they can't complete there order, which is obviously killing us - The site is slow. Like really slow. I tested it and it took forever to load - We added a bunch of apps over time and I'm sure half of them are conflicting with each other - Product photos are all different sizes so the collection pages look messy - There's no reviews showing even though we have a review app installed, can't figure out why We don't need it to look like some fancy agency built it. We just need it to work, load fast, and stop losing us sales. Honestly we've been putting this off for months because we don't have time to figure it out ourselves and we're scared of breaking it more. If your someone who actually knows Shopify inside and out and can go in and fix this stuff without us having to hold your hand, please reach out. We'd rather pay someone who knows what they're doing then keep guessing. If it goes well we probably have more we'll need down the line.