Its always difficult to buy an old car. I looked for 18 months before I found my the BJ8 I ended up buying. I must admit I looked for cars in Denmark and there are very few to choose from, so you have to wait long for the right model to show, I also looked in USA, but it seemed to risky to buy a car unseen.
When looking in USA in 2009, I discovered a good driver BJ8 ph 2, was for sale at around 38-45.000$. Below 35.000 looked to have way to many things that needed attention. I had some people help looking at the cars from pictures, and was warned by many problems on all the cars I looked at, in the end I almost lost interest in getting an Austin Healey, because of alle these warnings. It seemed like no matter what I bought I would get alot of problems.
In 2010 I found this car in Denmark,
https://www.fantasyjunction.com/cars/544-Austin-Healey-3000%20Mk.%20III%20Phase%20II-Inline%206%20Cyl with freshly rebuilt engine for 46.000$. I know it was bought in USA in late 2006 for 38.000$. Transportation, importtaxes etc, make them abit more expensive in Denmark than USA.
I decided it didnt mean that much to me if the price was 40.000 or 46.000, if it was the right car for me. I plan to keep it for many years, and if it cost abit more or less doesn't mean anything in the long run.
So as you say, follow the market and strike when the right car shows. Have some patience, and go see some cars to get an idea of what kind of condition you get for the price you want to pay.
And always look below the car for rust, the sellers rarely show pictures from below.
Niels