Hello, trained luthier here
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I spent about 6 years making and repairing guitars. Mostly repair though because honestly that's where reliable turnover is.
I think it's good to be clear about what you really want. It's so easy to fall into a trap of building an entire guitar around one special concept - for instance your favourite neck profile - and find the finished product doesn't have the same magic. Not that I want to put the idea down, but it sounds like you have a few itches to scratch. It might be sound to scratch a couple separately e.g. if you want to invest in a special guitar that's unique to you, that's a sound idea. Owning a handmade instrument is a great goal to aim for and achieve, there's definitely a lot of meaning for you if your guitar is really really personal. Making a guitar yourself, or learning the skills, might be a separate endeavour to enjoy.
How are you with woodwork generally? If you already have a few tools and would be happy buying/owning a few more general tools, plus some specialist ones, great. You will find you can start new projects easily if you enjoy the process. But if you will spend a good chunk of your planned budget on tools, only to use them once, the idea of a course might be more fitting so the budget goes towards wood and expertise more than tools. Likewise if you really really love that neck profile but don't feel the need to spend £1000+ on specialist tools (fretwork is the most niche bit of guitar making, requiring several special tools and techniques)... You could have a talented luthier make you a neck, and do the body yourself. All about figuring out whether it's the end result, or the journey, that you're interested in.
And what I would say about finding someone to work with, is look at the work they do rather than their location. As mentioned, asking a spiky, exotic wood type guitar guy to make you a classic maple 6 string may be playing to neither party's interests. Any luthier worth their salt will spend some time to understand your needs and desires, and try to make a product you will love. That can be over a few phone conversations, you could even post them the RT650 neck if it comes down to it. I've made just necks or just bodies for customers in the past and it's no less special than a whole guitar.
Also, poplar is an interesting one... Most Ibanez guitars tend to be basswood. Also known as lime. Also known as poplar. Different names around the world and maybe slightly different species, but very similar wood. You can get dense basswood or light basswood which has much less sustain and resonance. Unfortunately a lot of cheap Chinese guitars, especially kit guitars, are made of cheap poplar/basswood/paulownia and give it a bad name. Look for a good piece of wood, not just the right species.
Also bear in mind many luthiers will take pay by instalment, so you could have a custom order on the go for a year while you're designing and making something yourself. Sorry, essay over
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