The banks in Thailand aren’t targeting investors for growth. It’s for service. Thais invest in real estate. So for growth I suggest keeping your western account.
for the LTR I did not use an attorney. Only an agent. For my non-O I used a lawyer. It was helpful in so much as I was able to focus on other things (in that case it was chartering a boat for my birthday). I agree with other commenters that you don’t need anybody to apply for an LTR.
yes about 120-150K. It makes sense if time is money. Usually pensioners need no help whereas those living off investment income appreciate it. For instance I needed to supply proof of real estate investments and let my agent work with my lawyer back home while I was traveling. Super convenient.
I am on the LTR and used Star which is one of the five agents authorized by BOI. I was their first client to obtain the LTR and we learned together. For lawyer I use Sam at ILO who did my original visa and my 30 lease as well as my other leases. He is solid in my experience.
Most any country with the time will require proof of funds for residence. Tourists, not so much. Usually you hear this complaint from first time expats.