Welcome to the mud! And congrats on finding a nice example. Depending upon how it has been taken care of - I will hold off on the mods and plan on taking care of any deferred maintenance. If you are willing to get your hands dirty (and have some time to invest) you will save major bucks on labor. If you take it in for service - beware of run-of-the-mill shops who will create more issues than solve them. That's just the nature of the beast unfortunately.
Parts prices range from surprisingly affordable to you-gotta-be-shi++ing-me expensive.
The leaky windshield is typically due to bad glass installation - hopefully you don't have rust around the frame. Find a local installer and give them a copy of the windshield install pages to take it off and install it properly.
Check if any of these have been done recently: (all prices are for parts only)
Timing Belt - About $500 + $700 in labor
CV Axle (only is they are leaking) - $900
Rear control arms: $700
Front upper control arm $700
Front lower ball joints: $100
Shocks: $200 for all four Toyota originals!!
Front wheel bearings: $250
Brake rotors and pads: $600
Driveline fluids/grease: $150
Things that go bad around this mileage (bonus if it has taken care of already): Steering rack, tie rod ends, Brake booster assembly ($2000 to $3000 repair

), rear AC lines if there is rust.
So plan for around $5000 in maintenance and tires in the first year of ownership (unless of course some of these were taken care of by the prev. owner).
As for the mods - I always suggest driving it for a while before deciding what you actually want from your truck. No point in lifting it and adding big tires if that if that is not the intended use!